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We previously showed that individuals with seasonal allergic rhinitis (SAR) had a reduced ability to condition air, which was improved by inflammation. We hypothesized that individuals with perennial allergic rhinitis (PAR) would condition air like SAR with inflammation. Because individuals with asthma usually have inflammation in the nose, we hypothesized that they would condition air like individuals with PAR. We performed a prospective, parallel study on 15 normal subjects, 15 subjects with SAR outside their allergy season, 15 subjects with PAR, and 15 subjects with asthma. Cold, dry air (CDA) was delivered to the nose and the temperature and humidity of the air were measured before entering and after exiting the nasal cavity. The total water gradient (TWG) was calculated and represents the nasal conditioning capacity. The TWG in the SAR group was significantly lower than that in normal subjects. There were no significant differences in TWG between the PAR and normal groups. Subjects with asthma had a significantly lower TWG than did normal subjects. There was a significant negative correlation between TWG and Aas score in the group with asthma (r(s) = -0.8, p = 0.0007). Our data show that subjects with asthma have a reduced ability of the nose to condition CDA compared with normal subjects, but which is similar to SAR out of season.

Objective: To evaluate whether 1 year of continuous treatment with intranasal fluticasone propionate would lead to atrophy in the nasal mucosa compared with an active control, oral terfenadine., Design: Prospective, randomized, multicenter, open-label, parallel-group study., Setting: Two tertiary care academic institutions., Patients: Seventy-five subjects older than 18 years with perennial allergic rhinitis., Interventions: Patients received either fluticasone propionate aqueous nasal spray, 200 microg once daily, or terfenadine, 60 mg twice daily, for 1 year. Nasal biopsy specimens were obtained before and after 1 year of treatment and were evaluated for evidence of atrophy., Main Outcome Measures: Epithelial and collagen layer thickness of the nasal mucosa as assessed by light microscopy and the presence and degree of edema, and regularity of collagen fibrils as assessed by electron microscopy. Analyses were performed without knowledge of subject identity or treatment assignment., Results: Neither fluticasone nor terfenadine treatment led to atrophy in the nasal mucosa by clinical or histologic observation. No significant changes from baseline were observed for any assessment of atrophy. In contrast to what would have been expected if atrophy were to occur, mean epithelial layer thickness in the fluticasone group significantly increased compared with terfenadine treatment (P = .03)., Conclusions: Treatment with intranasal fluticasone for 1 year increases the thickness of the nasal epithelium as compared with a year's treatment with terfenadine and does not lead to atrophy in the nasal mucosa. The increased thickness in the fluticasone treatment may represent repair from epithelial damage caused by chronic allergic inflammation.

The nose functions to warm and humidify inspired air. The factors that influence these functions have been studied to a limited degree. We have developed a method for measuring the temperature and relative humidity of the air before and after nasal conditioning to study nasal function. In this experiment we studied the effects of raising the mucosal surface temperature by immersion of the feet in warm water. Six subjects (avg. age = 27.0 years) were randomized to immersion of the feet in 30 degrees C and 40 degrees C water. The nasal mucosal temperature increased significantly from the 32.2+/-1.3 degrees C during immersion in the 30 degrees C water to the 33.1+/-1.2 degrees C during immersion in 40 degrees water (p < 0.05). No significant difference in nasal volume was noted between the 30 degrees (17.8+/-4.5 cc) and the 40 degrees (17.7+/-5.3 cc) immersions. There was a significant increase in the conditioning capacity of the nose (as measured by total water content of inspired air) in response to cold-air challenge during the 40 degrees immersion (1669+/-312 mg water) when compared to the 30 degrees immersion (1324+/-152 mg water). From these data we deduce that warming of the nasal mucosa improves the ability of the nose to condition inspired air without a significant change in the volume of the nasal cavity.

We have developed a method for measuring the temperature and relative humidity of air prior to and after nasal conditioning and used it to study the effect of treatment with ipratropium bromide on the ability of the nose to condition cold, dry air. We performed randomized, double-blind, placebo-controlled, two-way crossover studies and an open study in nonallergic subjects. The subjects were treated with ipratropium bromide (84 microgram) or normal saline solution sprayed into the nasal cavity 15 min before the measurement of nasal conditioning capacity. Cold, dry air was delivered to the nose via a nasal mask, and the temperature and humidity of air were measured before entering and after exiting the nasal cavity. The total water gradient across the nose was calculated and represents nasal conditioning capacity. Ipratropium bromide treatment significantly increased nasal conditioning capacity when compared with saline. Ipratropium bromide led to less reduction in the cold, dry air-induced decrease in the nasal volume (p < 0.05) without affecting the decrease in nasal surface temperature during cold, dry air exposure (p = 0.3). Our data show that ipratropium bromide increases the ability of the nose to condition cold, dry air. Thus, treating rhinitis with ipratropium bromide should not increase the burden for inspired air conditioning on the conducting pulmonary airways.

Background: We have previously reported that preconditioning allergic subjects with hot, humid air (HHA) (temperature, 37 degrees C; relative humidity >95%) in an environmental chamber resulted in partial inhibition of the early response to nasal allergen challenge., Objective: To investigate whether this inhibitory effect could be achieved by inhalation of HHA via a face mask., Design: Randomized, 4-way crossover study., Subjects: Eighteen subjects with seasonal allergic rhinitis participated in the study outside of their allergy season., Interventions: Subjects underwent preconditioning with room air (RA) (temperature, 25 degrees C; relative humidity <20%) or HHA either in a chamber or delivered via a face mask for 1 hour prior to and during nasal challenge with diluent for the allergen extract followed by 2 increasing doses of allergen., Results: Net changes from diluent challenge for all parameters were compared between HHA and RA in each delivery method. Hot, humid air delivered by mask significantly inhibited the mean+/-SEM number of allergen-induced sneezes (HHA, 2.7+/-0.6; RA, 6.6+/-2.1; P=.03), congestion score (HHA, 2.3+/-0.5; RA, 3.4+/-0.5; P=.01), and secretion weights (HHA, 26.9+/-4.4 mg; RA, 38.6+/-5.0 mg; P=.048). However, HHA inhaled in a chamber significantly inhibited only the mean+/-SEM allergen-induced congestion (HHA, 1.2+/-0.4; RA, 3.6+/-0.6; P=.002) and pruritus (HHA, 0.7+/-0.3; RA, 2.3+/-0.5; P=.002) scores., Conclusions: Preconditioning the nasal mucosa with HHA partially decreases the early response to nasal challenge with antigen irrespective of the administration technique. The secretory response, however, is only inhibited by localized delivery of HHA to the nose. The inhibitory effects of HHA are therefore probably related to local changes in the nasal mucosa and are not dependent on total body exposure to HHA.

Background: We have previously shown that hot, humid air partially reduces the early allergic response. Mechanisms for this effect have been suggested, but none has gained universal acceptance. The most likely explanations are a modification of mucosal temperature or a reduction in nasal secretion osmolality., Objective: We sought to investigate whether increasing the nasal mucosal surface temperature by immersing feet in warm water (WW) could decrease the immediate nasal response to challenge with allergen., Methods: We performed a randomized, 2-way crossover study on 14 subjects with seasonal allergic rhinitis outside of their allergy season. They immersed their feet in either WW (42 degrees C) or room-temperature water (RW; 30 degrees C) for 5 minutes before and during nasal challenge with diluent for the allergen extract, followed by 2 increasing doses of allergen., Results: There was a statistically significant increase in nasal mucosal temperature from baseline after warming of feet (WW, 1.9 +/- 0.1 degrees C, vs RW, 0.2 +/- 0.1 degrees C; P =. 001), but there were no significant differences in body temperature (WW, 0.1 +/- 0.1 degrees C, vs RW, 0.4 +/- 0.1 degrees C; P =.1). Net changes from diluent challenge for all parameters were compared between immersion of feet in WW and RW. Immersion of feet in WW significantly inhibited allergen-induced sneezes (WW, 5.7 +/- 1.1, vs RW, 11.6 +/- 3.2; P <.01), human serum albumin levels (WW, 941.7 +/- 172.2 microg/mL vs RW, 1524.8 +/- 220.6 microg/mL; P <.01), and secretion weights (WW, 30.5 +/- 7.2 mg, vs RW, 41.8 +/- 6.8 mg; P <. 01)., Conclusion: Our data show that warming of feet decreases the early response to nasal challenge with antigen. This inhibitory effect is probably related to the increase in the nasal mucosal temperature.

Previous investigations have suggested that nasal secretions, obtained by lavage or scraping, and the nasal submucosa, sampled by biopsy, are two distinct compartments. We investigated the effect of intranasal corticosteroids on antigen-induced eosinophil influx into both compartments. We performed a double-blind, placebo-controlled study in 15 patients with seasonal allergic rhinitis. Beclomethasone dipropionate, 84 microg twice a day, was delivered to one nostril while the other nostril received placebo for 1 wk. Subjects were then challenged with grass or ragweed extracts on each inferior turbinate. Nasal scrapings from both inferior turbinates were obtained before and 24 h after challenge, and bilateral inferior turbinate biopsies were obtained 24 h after challenge, with the subjects still receiving treatment. Intranasal steroids led to a significant reduction in sneezes and eosinophil influx in nasal secretions without affecting the number of eosinophils in the submucosa. Furthermore, intranasal steroids had no effect on the numbers of submucosal EG2+ (activated eosinophils) or CD25+ (IL-2-receptor-bearing) cells, nor did they decrease the endothelial expression of vascular cell adhesion molecule-1 (VCAM-1). These data show that pretreatment with intranasal steroids successfully inhibited the clinical response to allergen and reduced eosinophils in the superficial compartment of the nasal mucosa, but it had no effect on inflammation in the deeper compartment. This might be related to a different distribution of the active medication and antigen into the nasal mucosa or to a specific effect of the active medication on the epithelium resulting in inhibited migration of eosinophils across this layer.

Background: Neuronal involvement has been implicated in the pathophysiology of non-allergic and allergic rhinitis, contributing to the typical exacerbation of these conditions upon exposure to non-specific environmental irritants., Objectives: To determine if non-allergic and allergic rhinitis are characterized by increased responsiveness of the nasal mucosa to sensorineural stimulation., Methods: Nasal challenges with capsaicin and its vehicle were performed in three groups of subjects -- non-allergic rhinitics, perennial allergic rhinitics, and healthy controls -- and resultant symptom scores, glandular secretion reflected by lactoferrin levels, and plasma extravasation reflected by albumin levels in nasal lavage fluid were compared., Results: Capsaicin-sensitive nerve stimulation produced increases in symptom scores and lactoferrin levels which were similar among the three groups of subjects. On the other hand, only the group of subjects with allergic rhinitis demonstrated a significant capsaicin-induced increase in albumin levels and a trend in total protein levels., Conclusions: We conclude that non-allergic rhinitis is not characterized by increased responsiveness of capsaicin-sensitive nerve fibres; while allergic rhinitis is marked by hyperresponsiveness manifested as increased albumin leakage in nasal fluids. This may reflect the activity of an axonal reflex to sensorineural stimulation.

Background: Clemastine (1 mg) is currently available over-the-counter for the treatment of allergic rhinitis., Objective: To evaluate the efficacy of half the standard dose of clemastine (0.5 mg) in inhibiting the nasal response to allergen and the cutaneous response to histamine., Methods: Double-blind, placebo-controlled, crossover study of 20 allergic subjects out of season. The subjects received placebo or clemastine administered one, four, and six hours before the challenges. Filter paper discs were used both to challenge the nasal mucosa with diluent and allergen and collect generated secretions. Sneezes, secretion weights, nasal and ocular symptoms, and albumin levels in nasal secretions were monitored for the nasal challenge. Intradermal skin testing was performed with diluent followed by histamine and the wheal and flare reactions were measured., Results: There was a significant reduction in the number of sneezes after clemastine administered one, four, and six hours prior to challenge compared with placebo (P < .01). Clemastine administered four and six hours before challenge reduced sneezing significantly more than clemastine administered one hour before challenge (P < .05). Antigen-induced increases in secretion weights and symptoms of rhinorrhea were significantly reduced compared with placebo only when clemastine was administered four and six hours prior to challenge (P < .05). Pretreatment with clemastine had no significant inhibitory effects on other nasal symptoms or on albumin levels in nasal secretions, an objective index of increased vascular permeability. Pretreatment with clemastine did not inhibit the histamine-induced wheal skin reaction but showed a tendency, when administered six hours prior to the intradermal challenge, to reduce the flare reaction induced by the lowest dose of histamine (P = .05)., Conclusions: The data show that clemastine, given at half the usual dose four and six hours prior to allergen challenge, provides relief for sneezing and rhinorrhea and suggests that this dose might be useful in the treatment of allergic rhinitis.

Ten subjects with asymptomatic seasonal allergy, outside of their allergy season, underwent allergen provocation following 1 hour of exposure to air at either 20 degrees C and 30% relative humidity (RH) or air at 37 degrees C and 90% RH. The ipsilateral changes following antigen challenge were compared under the two conditions. Conditioning of the nose to 37 degrees C, 90% RH reduced total histamine release (7.9 +/- 1.8 ng vs 4.2 +/- 1.3 ng; p < or = 0.05), sneezes (6 +/- 2 vs 3 +/- 1; p < or = 0.05), pruritus (score of 17.4 +/- 6.0 vs score of 2.0 +/- 1.8 out of a total score of 100, p < or = 0.01), nasal airway resistance (1.4 +/- 0.8 kPa/L/sec vs 0.2 +/- 0.1 kPa/L/sec; p < or = 0.05), human serum albumin levels (389.6 +/- 53.4 micrograms vs 242.2 +/- 37.9 micrograms; p < or = 0.05), and congestion (score of 23.8 +/- 4.8 vs score of 10.6 +/- 5.4 out of a total score of 100, p < or = 0.01). It had no effect on the volume of secretions (p = 0.8), lactoferrin levels (p = 0.3), or rhinorrhea (p = 1.0). Thus air at 37 degrees C and 90% RH partially reduces the early response to antigen. Its effects are greatest on histamine release, the vascular response, and neural responses, with no effect on the glandular response. The mechanisms underlying these effects are unknown.

Objectives: To quantitate lymphocyte subtypes in sinus tissues harvested from children with chronic sinusitis and coexisting asthma, allergies, and cystic fibrosis during functional endoscopic sinus surgery and compare them with those in normal adult sphenoid sinus mucosa., Design: Immunohistochemical staining of surgical specimens with monoclonal antibodies against CD4 and CD8 surface antigens., Setting: Tertiary medical center., Patients: Thirty-two children who underwent functional endoscopic sinus surgery for chronic sinusitis refractory to medical treatment (median age, 8 years; range, 2-13 years) were divided into 3 groups: 10 with asthma, 15 without asthma, and 7 with cystic fibrosis. Sphenoid sinus mucosa obtained from 10 adults (median age, 70 years) undergoing transsphenoidal hypophysectomy was used as control tissue., Main Outcome Measures: Numbers of CD4+ and CD8+ cells in the lamina propria and epithelium of surgical specimens., Results: Significantly more CD4+ cells were in the sinus mucosa of patients with chronic sinusitis than in the normal sinus mucosa (P < .01), but there was no significant difference in the number of CD8+ cells (P = 4). Patients with chronic sinusitis with asthma, without asthma, and with cystic fibrosis all had increased numbers of CD4+ cells compared with sphenoid mucosa, with the difference reaching statistical significance only in the subgroup with chronic sinusitis without asthma (P < .001). The numbers of CD4+ cells were higher in patients with chronic sinusitis than in the sphenoid mucosa irrespective of allergic status. Significantly more CD4+ than CD8+ cells were in tissues from the patients with chronic sinusitis irrespective of concomitant diseases or allergic status. CD4+ and CD8+ cells were more numerous in the apical portion of the submucosa (immediately beneath the epithelium) than in the basal portion both in patients with chronic sinusitis and in normal sphenoid tissue., Conclusions: Children with chronic sinusitis have predominance of CD4+ cells in the sinus mucosa as compared with normal sphenoid tissue. This contrasts with published results in adults with chromic sinusitis, in whom CD8+ cells predominate in nasal polyps and the submucosa, possibly reflecting a difference in the immunologic response of children and adults.

The present studies were undertaken as a first step to evaluate the potential usefulness of the bradykinin antagonist HOE-140 in delineating the role of kinins in the pathogenesis of chronic rhinitis. Intranasal single-dose administration of HOE-140, at doses up to 500 micrograms, was safe and well tolerated. Bradykinin-induced symptoms and increased vascular permeability could be inhibited, in a dose-dependent manner, by preadministration of HOE-140 5 min prior to kinin challenge. The results of dose-ranging experiments suggested that bradykinin and HOE-140 were approximately equipotent at bradykinin receptors. Preadministration of HOE-140 2 h before kinin challenge caused a significant but much weaker level of inhibition than that seen with 5-min preadministration. Comparison of data with those obtained during dose-ranging studies suggested that more than 90% of the administered HOE-140 was lost during this 2-h period. We conclude that topical HOE-140 is an effective inhibitor of the effects of bradykinin on the nasal mucosa but that the short duration of action of this drug may severely limit the utility of HOE-140 in delineating the role of kinins in the pathogenesis of chronic rhinitis.

Background: The parasympathetic nervous system plays an important role in the nasal response to external stimuli., Objective: To review studies showing the role of the parasympathetic nervous system in the nasal response and the effect of topical, intranasal anticholinergic agents on that response., Method: Literature review of in vivo human studies., Results: Nasal provocation with methacholine leads to glandular stimulation. The response to methacholine provocation can be blocked by treatment with ipratropium bromide. Stimulation of one nostril with histamine, antigen, and cold, dry air leads to a bilateral secretory response that is partially inhibited by topical treatment with atropine., Conclusion: Topical anticholinergic agents should be useful in the reduction of glandular hypersecretion regardless of the etiology.

To understand the events involved in selective eosinophil migration into allergic inflammatory sites, we studied the expression of vascular endothelial adhesion molecules in the nasal mucosa. Ten subjects with asymptomatic seasonal allergic rhinitis and 13 nonallergic subjects underwent localized allergen challenge of one inferior turbinate. Twenty-four hours later, biopsy specimens were obtained from the inferior turbinates, bilaterally in the seasonally allergic subjects and unilaterally in the nonallergic control subjects. The specimens were divided, sectioned, and either stained for identification of eosinophils or analyzed immunohistochemically for intercellular adhesion molecule-1, E-selectin, vascular cell adhesion molecule-1 (VCAM-1), and von Willebrand's factor. Intercellular adhesion molecule-1 expression was observed in all mucosal specimens, with no significant difference among groups. E-selectin showed minimal baseline expression, and low levels were significantly induced on the challenged mucosa of the allergic compared with nonallergic subjects (p < 0.05). VCAM-1 was expressed basally and was significantly upregulated by allergen challenge, compared with the nonchallenged side and nonallergic control subjects (p < 0.05). Submucosal eosinophils increased significantly in allergic subjects 24 hours after antigen challenge, compared with nonallergic control subjects and weakly correlated with VCAM-1 expression (rs = 0.33, p = 0.06). Our results suggest that endothelial activation accompanies allergic inflammation. Furthermore, because the counterligand for VCAM-1, very late activation antigen-4, is present on eosinophils, VCAM-1 upregulation may contribute to the selective recruitment of these cells to the nasal mucosa.

Airway sensory nerves play a role in reactions to inhaled allergens, irritants, and physical stimuli. Capsaicin, the pungent principle of hot peppers, stimulates a subcategory of sensory nerves. To study the consequences of selective activation of airway sensory nerves in the human nose, we administered capsaicin nasal challenges to eight volunteers (four normal subjects and four subjects with perennial allergic rhinitis). Capsaicin (20 mumol/L), when sprayed into the nose, induced burning, rhinorrhea, and lacrimation. Capsaicin also induced a significant increase in total protein content of nasal lavage fluid after challenge compared with vehicle (increase from before challenge to 1 minute after challenge, 172 +/- 55 vs 46 +/- 29 micrograms/ml, p < 0.001). In contrast to many animal studies, capsaicin did not increase vascular permeability in the airway, because albumin content of nasal lavage fluid was not increased (p = 0.86). On the other hand, lactoferrin, a marker of glandular secretion, was increased (p < 0.005). Repetitive capsaicin challenge every 10 minutes led to tachyphylaxis of symptoms, total protein secretion, and lactoferrin secretion. Compared with vehicle, unilateral capsaicin (6 mmol/L) disk challenge induced significant secretion both ipsilateral (21.3 +/- 4.2 vs 4.9 +/- 2.1 mg, p < 0.01) and contralateral (18.2 +/- 4.4 vs 7.4 +/- 1.9 mg, p < 0.04) to challenge. Thus we have shown that capsaicin challenge to the human nose leads to airway sensory nerve activation. Further, we have demonstrated that capsaicin stimulates a predominantly central neuronal response and that the induced secretory response is of glandular rather than vascular origin.

Allergic rhinitis is the sixth most prevalent chronic health condition in the United States. To study the pathogenesis of the allergic response, we have used a model of nasal provocation with antigen. During the initial reaction of an allergic subject to allergen provocation, increases occur in the levels of histamine, tryptase, and prostaglandin D2. This pattern of mediator release, combined with histologic evidence of mast-cell degranulation, strongly supports the role of the mast cell in the acute allergic reaction. The response to antigen, however, does not end with mast-cell degranulation. Hours after challenge we observed the spontaneous recurrence of symptoms and increased responsiveness to antigenic and nonantigenic stimuli. Our central hypothesis is that cellular infiltration and activation after antigen challenge are responsible for the observed increase in nasal reactivity. The predominant cells in nasal lavage 24 hours after challenge are eosinophils and neutrophils, whereas the predominant cell in the mucosa is the CD4+ lymphocyte. An early step in the movement of cells from the peripheral blood involves adhesion between circulating leukocytes and the endothelium. Evidence suggests that vascular endothelial adhesion molecule may be responsible in part for the selective adherence of eosinophils to the endothelium.

We performed a randomized, double-blind, placebo-controlled cross-over study with two different concentrations of ipratropium bromide (Atrovent) nasal spray to evaluate its onset and duration of inhibition. Twenty-four subjects with perennial rhinitis participated in the trial. Fifteen minutes to 12 hours after administration of ipratropium bromide (42 or 168 micrograms/nostril) or placebo nasal spray, methacholine challenges were performed and nasal secretion weights measured. After placebo administration the effect of methacholine remained unchanged over the 12-h-period. Both the 42 and 168 micrograms/nostril doses significantly inhibited the nasal hypersecretions induced by methacholine challenge within 15 min of treatment (P < 0.05). The 168 micrograms dose of ipratropium bromide continued to significantly reduce secretion weights through 6 hours, but the effectiveness of the 42 micrograms dose disappeared within 3 h. In addition to having a longer duration, the 168 micrograms/nostril dose produced approximately twice the inhibitory effect of the 42 micrograms dose.

Exposure to cold dry air induces rhinorrhea and other nasal symptoms in many persons. To evaluate whether this response involves a neurogenic component, we delivered a unilateral cold dry air (UniCDA) nasal challenge to volunteers with previously documented reactivity to cold dry air. We measured their nasal secretory responses bilaterally using small filter paper discs to absorb secretions from the nasal mucosa. UniCDA increased nasal secretion both ipsilateral (p < 0.001) and contralateral (p < 0.001) to the challenge when compared with control challenge. Topical atropine (0.225 mg), a muscarinic antagonist, inhibited ipsilateral secretion (p < 0.002) when given ipsilateral to UniCDA. When atropine was given contralateral to UniCDA, there was a trend toward reduction of contralateral secretion but no effect on ipsilateral secretion. Topical anesthesia with lidocaine given ipsilateral to UniCDA inhibited ipsilateral (p < 0.02) and contralateral (p < 0.05) secretion immediately after challenge. Topical anesthesia did not inhibit methacholine-induced nasal secretion. Thus, UniCDA stimulates reflex secretion both ipsilateral and contralateral to challenge which is inhibitable by interrupting either the efferent or the afferent arm of the reflex arc. This human in vivo model supports the importance of neural mechanisms in airway responsiveness to an environmental stimulus.

Cold, dry air (CDA) causes rhinorrhoea and nasal congestion in some individuals. This response can be mimicked in the laboratory by exposing susceptible individuals to cold, dry air nasal breathing. One of the characteristics of this response is that nasal secretions are produced by both nostrils after a unilateral challenge. This study evaluated the role of cholinergic innervation on the ipsi- and contralateral responses to unilateral CDA challenge. Twelve individuals participated in a randomized, double-blind, placebo-controlled, 3-way crossover study where local atropine and placebo were alternated ipsilateral and the contralateral to the CDA challenge. The reproducibility of the model, assessed by the response after pre-treating with placebo, was excellent; after placebo, the ipsilateral response was double the size of the contralateral. Regardless of the site of application, atropine significantly reduced the secretory response to CDA by 60-70%. However, significant secretions were still induced by CDA, even after atropine treatment. We conclude that cholinergically-mediated neuronal pathways play a major role in the nasal secretory response to CDA. Additional neuronal pathways may, however, be involved. This method is a tool to understand the different components of the mucosal response to a cold and dry environment.

To better understand the secretory response of the nasal mucosa, we must be able to accurately measure its physiological response. To this end, we developed a localized challenge technique using paper disks to stimulate the mucosa on one side and measure secretions from both sides to study both direct and reflex responses. Both methacholine and histamine induced a dose-dependent increase in secretion weights on the challenge side, whereas only histamine induced a contralateral reflex. Repeated stimulation with histamine, but not methacholine, resulted in tachyphylaxis. Pretreatment with atropine resulted in inhibition of the contralateral secretory response to histamine and the ipsilateral response to methacholine with only partial inhibition of the ipsilateral histamine response. Terfenadine pretreatment resulted in the complete inhibition of both the ipsilateral and contralateral responses to histamine with no effect on methacholine-induced secretions. Ipsilaterally applied lidocaine had no effect on the histamine response but, when applied contralaterally, partially inhibited that response. Topical diphenhydramine applied ipsilaterally led to significant inhibition of the ipsilateral and contralateral secretory responses to histamine but had no effect when applied contralaterally. We conclude that methacholine and histamine have different effects on the nasal mucosa. We speculate that methacholine stimulates glands directly, whereas histamine includes both direct and neurogenic stimulation.

We have developed a new technique for the direct local administration of test solutions to the nasal mucosa and for quantification of nasal secretory responses. This technique, a variation on several published reports of filter paper use, allows simple and rapid determination of drug effects and facilitates the analysis of ipsilateral and contralateral responses to local challenge of the nasal mucosa. We have used this technique to investigate the secretory responses of the nasal mucosa to methacholine and histamine and to determine the effects of atropine and ipratropium bromide (Atrovent nasal spray) on these secretory responses.

A nasal lavage model and a new filter paper disk model have been used to measure biologic and physiologic responses to antigen challenge in patients with allergic rhinitis. Pretreatment of subjects with cetirizine reduced the number of sneezes induced by antigen challenge but did not significantly reduce levels of histamine or prostaglandin D2 in a double-blind, placebo-controlled trial with the lavage model. Pretreatment with 60 or 300 mg of terfenadine did significantly reduce levels of histamine, kinin, albumin, and TAME-esterase activity in a double-blind, placebo-controlled study with this model. Again with the nasal lavage model, a double-blind, placebo-controlled comparison of pretreatment with 60 mg of terfenadine or 10 mg of loratadine showed that both agents significantly reduced sneezing. Both drugs also lowered levels of antigen-induced histamine and TAME-esterase, but only terfenadine did so significantly. In a double-blind, placebo-controlled study, the new disk method showed that terfenadine reduced sneezing but not nasal congestion in eight patients with allergic rhinitis. Terfenadine significantly reduced the weight of nasal secretions on both sides of the nose and significantly reduced histamine on the ipsilateral side.

To determine whether intranasal steroid treatment inhibits the increased sensitivity to histamine that occurs 24 hours after nasal antigen challenge, 12 allergic volunteers were entered into a double-blind study comparing placebo or 164 micrograms of beclomethasone dipropionate twice a day for 7 days. Beclomethasone dipropionate partially reduced the early mediator response to antigen and the influx of eosinophils 24 hours later. Comparing the initial histamine challenge with that done 24 hours after antigen with the subjects on placebo, there was a significant increase in sneezes, TAME-esterase activity, and albumin. Pretreatment with intranasal beclomethasone dipropionate resulted in a reduced response to histamine 24 hours after antigen challenge. A positive correlation occurred between the number of eosinophils in the lavage before histamine challenge and the level of TAME-esterase activity (rs = 0.67, p = 0.03) during the histamine challenge that followed antigen with the subjects on placebo. We thus confirmed the increase in nonspecific nasal airway responsiveness 24 hours after antigen challenge, with a concomitant increase in eosinophils, and demonstrate its inhibition by pretreatment with intranasal steroids.

We investigated the efficacy of local ipratropium bromide on methacholine-induced nasal secretions in a double-blind, placebo-controlled experiment. Twenty subjects with perennial rhinitis received a total intranasal dose of 21, 42, 84, and 168 micrograms of ipratropium bromide or placebo in each nostril. One hour later, filter paper disks were used to deliver increasing doses of methacholine and to collect secretions from the left septum. Concomitantly, symptoms of rhinorrhea and nasal congestion were scored. Compared with doses of placebo, all doses of ipratropium bromide significantly reduced the methacholine-induced increase in nasal secretion weights and symptoms of rhinorrhea (p less than 0.01). The highest dose was significantly more effective than the lower doses in reducing secretion weights (p = 0.01). We speculate that ipratropium bromide may prove beneficial for the treatment of rhinorrhea in perennial rhinitis. Furthermore, increasing the delivered dose to 168 micrograms may increase efficacy without augmenting side effects.

We have used assays for histamine and for the specific mast cell enzyme, tryptase, to examine the response of the nasal mucosa to provocation with several different stimuli and to evaluate the reliability of histamine as a marker of mast cell activation. High levels of histamine detected in baseline lavages of some subjects are not associated with any detectable tryptase, suggesting they are not mast cell derived. During pronounced immediate allergic responses, however, mast cell degranulation clearly occurs, and a striking correlation between histamine and tryptase is observed. This correlation is weaker when a more modest allergic response is induced, possibly reflecting differential diffusion of the two mediators across the epithelium. Provocation of susceptible individuals with cold, dry air leads to increased recoveries of both histamine and tryptase, confirming that mast cell degranulation occurs during this reaction. Although hyperosmolarity of the nasal mucosa may contribute to mast cell degranulation induced by cold, dry air, a brief exposure of the nasal cavity to hyperosmolar mannitol was not associated with measurable production of tryptase. The combined use of histamine and tryptase measurements can therefore provide useful evidence regarding the role of mast cell activation in the pathogenesis of inflammatory responses.

The pattern of mediators and appearance of cells that stain with alcian blue during human experimental early and late phase allergic reactions suggest that basophils accumulate in nasal secretions within hours of local Ag stimulation. To further explore whether the histamine containing cells that enter the nose after Ag challenge are mast cells or basophils, we studied their functional and phenotypic characteristics. Approximately 24 h after intranasal Ag provocation of subjects with allergic rhinitis, nasal lavage was performed, and the cells were isolated for degranulation studies, analysis of surface Ag, and viability. The average histamine content per alcian blue staining cell was 0.78 +/- 0.2 pg (n = 7), similar to that reported for peripheral blood basophils. Nasal cells were challenged in vitro with anti-IgE, ragweed Amb a I, and FMLP and their responses were compared to those of peripheral blood basophils isolated simultaneously from the same donors. Nasal leukocytes released histamine maximally at 0.1 micrograms/ml of anti-IgE (35.8 +/- 7.8%, n = 7) and responded to FMLP (25.4 +/- 9.9%, n = 7). The response of the cells to ragweed Amb a I and anti-IgE was attenuated compared to peripheral blood basophils. Anti-IgE-induced histamine release was calcium and temperature dependent. Dual color immunofluorescence and flow cytometric analysis of the recovered nasal cells coexpressed CD18, a leukocyte marker not expressed by mast cells. The nasal cells consistently had high levels of spontaneous histamine release (19.5 +/- 2.0%, n = 22). The viability of all cells, assessed by erythrosin B dye exclusion, was 70 +/- 2% (n = 15). However, the viability of IgE-bearing cells was only 28.3 +/- 5.7% (n = 4). The characteristics of histamine release and the nature of the cellular surface markers provide functional proof that the histamine-containing cells accumulating after nasal Ag challenge are basophils and not mast cells.

We have evaluated mechanisms by which nasal provocation with bradykinin may induce symptoms of rhinitis. Repeated nasal challenges with 100 micrograms of bradykinin led to reproducible increases in symptoms and in vascular permeability. Premedication with aspirin did not alter bradykinin-induced responses. Topical application of the alpha-adrenergic agonist oxymetazoline significantly reduced bradykinin-induced subjective nasal congestion scores, but did not lead to a significant decrease in total symptoms or in vascular permeability. Finally, the B1 kinin receptor agonist des-Arg9-bradykinin (1 mg) was totally ineffective in inducing symptoms or increasing vascular permeability. Thus, nasal provocation with bradykinin leads to induction of symptoms and increased vascular permeability, presumably via stimulation of B2 kinin receptors, and is not dependent on prostanoid generation.

To further define the role of histamine in the nasal mucosa, we studied the possible effect of histamine provocation on the generation of prostanoids and leukotrienes, and on the induction of hyperresponsiveness to methacholine. In separate experiments, we performed nasal challenges with histamine and measured by gas chromatography negative ion mass spectrometry and by radioimmunoassay after high-performance liquid chromatography the levels of prostanoids and leukotrienes, respectively, in recovered nasal lavages 10 min after challenge. Hyperresponsiveness to methacholine was tested in both nostrils 24 h after unilateral provocation with histamine. Our data suggest that histamine induced an immediate symptomatic response, but neither led to the generation of prostaglandins or leukotrienes nor induced hyperresponsiveness to methacholine. These results differ from those achieved after antigen stimulation and emphasize the importance of mediators in addition to histamine in the allergic reaction.

We have developed sensitive amplified immunoassays for measurement of IgE and IgG4 ragweed (RW) antibodies in unconcentrated nasal washes. IgE to Amb a I (formerly antigen E) can be assayed to less than 0.1 ng/ml using IgE capture by anti-IgE on microtitre plates and an alkaline phosphatase-conjugated Amb a I with an amplification substrate technique. IgG4 to whole RW extract was assayed to less than 0.01 ng/ml by amplification ELISA using monoclonal anti-IgG4. Nasal washes (NW) (10 ml) and serum were obtained in December from 22 RW-sensitive patients before and after 1 and 2 yr of RW immunotherapy (IT), and assayed for Amb a I IgE or RW IgE and RW IgG4 antibodies Amb a I IgE could be measured in the NW of 15/22 pre IT, 19/22 at 1 yr IT, but only 3/10 at 2 yr IT (compared with pre-IT, P less than 0.05). Mean Amb a I IgE in NW was 0.66, 0.36 and 0.21 ng/ml at pre, 1 yr and 2 yr IT (P-values greater than 0.05). Mean serum RW IgE, was 76, 55 and 27 ng/ml at pre, 1 yr and 2 yr IT (P-values greater than 0.05). Amb a I IgE in nasal washes was correlated with RW IgE in serum (r = 0.56, P less than 0.001, n = 44). RW IgG4 was detectable in NW of 15/22 pre-IT, 18/22 at 1 yr IT and 9/10 at 2 yr IT (P-values greater than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

A prospective study compared the levels of inflammatory mediators in nasal lavages from noninfected, asymptomatic subjects with the mediator content of lavages from the same subjects during naturally occurring rhinovirus colds. Samples were obtained from 16 subjects who experienced natural colds that could be attributed to rhinovirus infections. Kinin levels during symptomatic colds were significantly elevated (P less than .01) compared with those measured when the subjects were noninfected and asymptomatic. Increases in kinins correlated with increased vascular permeability, as monitored by increased concentrations of albumin in lavages. In contrast, histamine levels in nasal lavages were not increased during symptomatic infections, suggesting that mast cell and basophil activation does not occur during rhinovirus colds. These data confirm and extend observations made during experimentally induced rhinovirus infections to the natural disease and are consistent with the hypothesis that kinins may play a role in the pathogenesis of symptomatic rhinovirus infections.

We performed a double-blind, placebo-controlled, crossover study using 12 subjects to determine the effects of a single 50-mg dose of captopril on the response to nasal challenge with increasing doses of allergen. Levels of kinins, histamine and N-alpha-p-tosyl-L-arginine methyl ester (TAME)-esterase activity were measured in nasal lavages, and symptom scores and the number of sneezes were recorded. Captopril had no significant effects on histamine, TAME-esterase, sneezing or symptom scores. Peak postchallenge kinin levels, however, were significantly elevated (p less than 0.05) compared to placebo, while an increase in the magnitude of the dose-response curve was of marginal significance (p = 0.058). Thus, captopril causes increases in the kinin levels in nasal secretions during the allergic response. If increased kinin levels persist or worsen with chronic therapy, it is possible that they could exacerbate allergic symptoms during repeated seasonal exposure.

An in vivo model system was developed to recover inflammatory mediators from the nose after antigen stimulation. In 105 experiments involving 35 subjects, antigen was introduced into the nose. Allergic individuals demonstrated an increase concentration of histamine, TAMe esterase and PgD2 during the physiologic changes of nasal obstruction and sneezing. Clinical symptoms and mediator release were highly correlated; moreover, the release of each mediator was significantly correlated to the others.

Inhaling cold, dry air nasally induces in some persons symptoms of rhinitis that are associated with an increase in the level of mast-cell-associated mediators in nasal lavages. The present study, directed at understanding the mechanism of this reaction, showed that 9 subjects who displayed symptoms and inflammatory mediator release had significant (p less than 0.01) increments in nasal fluid osmolality, whereas the osmolality of the fluids of 6 subjects unaffected by cold, dry air challenge did not differ from baseline. Significant correlations were found between the mediator concentration and the osmolality of recovered nasal lavages (rs = 0.617, p less than 0.02; rs = 0.679, p less than 0.01 for histamine and TAME-esterase(s), respectively). No changes in the osmolality of nasal secretions were found in atopic subjects undergoing nasal challenge with antigen, despite the generation of symptoms and significant elevations in the levels of inflammatory mediators in their nasal lavages. Because increasing the osmolality of the medium surrounding isolated mast cells in vitro triggers mediator secretion, these observations support the concept that the response to cold, dry air nasal inhalation is caused by the release of mediators secondary to an increase in the osmolality of the mucosal secretions.

The effect of systemic glucocorticoid treatment on early- and late-phase nasal allergic reactions after allergen challenge was determined in a double-blind, cross-over study in 13 allergic individuals. The subjects were pretreated for 2 d before challenge with 60 mg prednisone per day or a matching placebo. A previously described model using repeated nasal lavages for measuring mediator release in vivo was utilized. Symptom scores obtained repeatedly before, during, and after the challenge and the number and timing of sneezes were recorded. The mediators measured were histamine. N-alpha-p-tosyl-L-arginine methyl ester (TAME)-esterase activity, kinins, PGD2, and LTC4/D4. Albumin was also measured as a marker of plasma transudation. Blood samples were taken for determination of total number of white blood cells, differential count, and total blood histamine content. No effect of steroid therapy was found on the appearance of symptoms or any of the mediators, except a reduction in kinins, in the early phase of the allergic reaction. However, in the late phase, the prednisone reduced the number of sneezes (P less than 0.01), as well as the level of histamine (P less than 0.05), TAME-esterase activity (P less than 0.05), kinins (P less than 0.05), and albumin (P less than 0.05). Only low levels of leukotrienes were found in the late phase, but the quantities of these mediators seemed to be decreased by the glucocorticoid treatment (P = 0.06). PGD2 did not increase during the LPR and thus was not affected by glucocorticosteroids. The immediate response to a second challenge 11 h after the first was also evaluated. Whereas the appearance of mediators was enhanced over the initial response to the same challenge dose in placebo-treated subjects, this enhancement was abrogated after prednisone treatment. As this dose of drug is known to be clinically effective in treating hay fever, the present study confirms the earlier findings of others that short-term systemic glucocorticoid treatment inhibits the late phase but not the immediate phase of antigen challenge. Furthermore, secondary enhancement of immediate responses is inhibited. This study shows that glucocorticoids inhibit the generation or release of inflammatory mediators during the late reaction and the physiologic response.

Patients with allergic rhinitis often have immediate symptoms after antigen challenge (the early-phase response), followed several hours later by a recurrence of symptoms (the late-phase response). Systemic glucocorticosteroids are known to inhibit the late-phase but not the early-phase response. We studied the effect of one week of pretreatment with topical (rather than systemic) glucocorticosteroids on the response to nasal challenge with antigen in a double-blind, randomized, placebo-controlled crossover study of 13 allergic patients who had previously had a dual response to nasal challenge. The patients were challenged with three 10-fold increments of allergen, producing an early response, and were then followed for 11 hours, encompassing the late response, before they were rechallenged with the lowest dose of allergen. We monitored their responses by means of symptom scores and measurements of the levels of histamine, tosyl-L-arginine methyl ester (TAME)-esterase activity, and kinins in nasal lavages. Topical glucocorticosteroids significantly reduced both the symptoms and the levels of histamine, TAME-esterase activity, and kinins in the early, late, and rechallenge allergic reactions. The fact that, in contrast to treatment with systemic glucocorticosteroids, prolonged pretreatment with topical glucocorticosteroids inhibited the early-phase response to antigen suggests that the route and duration of administration affect the mechanisms of action of the steroids. We conclude that inhibition of the early-phase as well as the late-phase response by topical glucocorticosteroids may provide an advantage over treatment with systemic glucocorticosteroids in patients with allergic rhinitis.

We have used a model of nasal provocation to study the effects of pharmacologic interventions upon various types of inflammatory reactions of the upper airways. Pretreatment of allergic individuals with aspirin reduces the levels of prostaglandins in nasal secretions during the immediate allergic response but has no effect on symptoms. Theophylline and azatadine both reduce symptoms and the levels of mast cell mediators during the allergic response. By contrast, azatadine has no effect on symptoms or mediator levels during the response to challenge with cold, dry air, suggesting different mechanisms of mast cell activation in response to allergen and cold, dry air. Both topical and systemic steroids are effective in reducing symptoms and mediators during the late allergic response, but topical steroids also significantly inhibit the immediate response. Nasal challenge provides a convenient, relatively noninvasive method to study inflammatory reactions of the upper airways.

We have previously demonstrated that azatadine, a tricyclic antihistamine, known also to inhibit mediator release from mast cells and basophils in vitro, inhibits the early release of histamine and other mediators after nasal challenge with antigen. In this article, we studied the effect of azatadine on preventing the release of histamine after nasal challenge with cold, dry air (CDA) and its effect on antagonizing nasal challenge with histamine. With histamine challenge, azatadine inhibited symptoms (sneezing, nasal congestion, and rhinorrhea) and the increase in the level of albumin in nasal secretions (p less than 0.01 all). With challenge with CDA, the drug had no effect on either symptoms or histamine and N-tosyl-L-arginine methyl ester-esterase release. Although the patterns of mediator release after CDA and after the early reaction to antigen are similar, the pharmacologic control differs, suggesting different mechanisms of induction of histamine release from mast cells.

Previous studies have demonstrated symptoms and mediator release occurring as long as 11 h after nasal challenge with antigen in selected allergic subjects. Pretreatment with systemic steroids reduced symptoms and mediators including histamine, TAME-esterase activity, and kinins. The aims of the present study were to characterize the cell influx during the late-phase response to antigen challenge and to determine the effect of pretreatment with systemic steroids on this response. We examined cytospin slides of nasal washings obtained before and hourly for 11 h after nasal antigen challenge in 10 asymptomatic allergic subjects with a history of seasonal rhinitis and 5 normal, nonallergic subjects. Allergic subjects received oral prednisone (20 mg 3 times a day) or placebo in a random, double-blind crossover manner for 2 days before each of 2 challenges 1 month apart. On placebo days, a mixed cell influx occurred in allergic subjects during the late response that was 50-fold greater than the cell influx in the nonallergic control subjects (p less than 0.005). During the first 3 h after antigen challenge, eosinophils (p less than 0.005), but not neutrophils or mononuclear cells, were observed. During the late phase (4 to 11 h), neutrophils, eosinophils, and mononuclear cells were all increased. Oral steroid pretreatment blocked the influx of eosinophils (p less than 0.005), but not that of other cells. These data demonstrate an inflammatory cell influx associated with the nasal late-phase response and suggest an important pathogenetic role for the eosinophil.(ABSTRACT TRUNCATED AT 250 WORDS)

We have previously demonstrated that a mixture of bradykinin and lysylbradykinin is generated in nasal secretions during the immediate allergic response to allergen. The present studies were performed to determine whether glandular kallikrein plays a role in kinin formation during the allergic reaction. Allergic individuals (n = 7) and nonallergic controls (n = 7) were challenged intranasally with appropriate allergen, and nasal lavages obtained before and after challenge were assayed for immunoreactive glandular kallikrein as well as for histamine, kinins, and N-alpha-tosyl-L-arginine methyl esterase (TAME-esterase) activity. The increase in postchallenge immunoreactive glandular kallikrein levels above baseline was significantly greater (p less than 0.01) for the allergic group (16.3 +/- 14 ng/ml; means +/- SD) than for the nonallergic controls (1.0 +/- 1.9 ng/ml). Increased levels of immunoreactive glandular kallikrein correlated with increases in kinins, histamine, and TAME-esterase activity and with the onset of clinical symptoms. Characterization of immunoreactive glandular kallikrein purified from postchallenge lavages by immunoaffinity chromatography confirmed the identity of this material as an authentic glandular kallikrein on the basis of its inhibition by protease inhibitors and by monospecific antibody to tissue kallikrein, its chromatographic behavior on gel filtration, and its ability to generate lysylbradykinin from highly purified human low m.w. kininogen. The specific activity of this purified material, in terms of kinin generation from kininogen, was very similar to that for authentic glandular kallikrein, suggesting that most if not all of the immunoreactive material purified from nasal lavages represented active enzyme. Inhibition studies by using pooled postchallenge lavages suggest that the majority of the kinin generating activity in these samples was due to glandular kallikrein. We conclude, therefore, that glandular kallikrein is secreted during the allergic response and can contribute to the formation of the lysylbradykinin produced during the allergic reaction.

Nasal challenge of susceptible persons with cold, dry air (CDA) (breathing air at a temperature of -7 to -10 degrees C and a relative humidity of 0 to 10% at a flow rate of 12.5 ml/min for 15 min) stimulates nasal symptoms and release of histamine and other mediators associated with mast-cell activation. To investigate whether such a nonantigenic stimulus induces a late-phase reaction (LPR) in the nose, we challenged 12 preselected volunteers who had previously shown an immediate response to CDA. We monitored the subjects' responses for 10 h by means of symptom diaries and the levels of histamine and TAME-esterase activity in nasal lavage fluids. All 12 subjects showed an immediate response, whereas 8 had a LPR, as indicated by a recurrence of symptoms (rhinorrhea and congestion) hours later, accompanied by an increase in the levels of histamine and TAME-esterase activity. Rhinorrhea and congestion were concomitant with the late reelevation of mediators. Control challenges of these subjects with warm, moist air (WMA), as well as serial nasal lavages without any stimulation of the nose, failed to induce an early- or a late-phase response. The amount of both mediators and symptoms generated during the 10 h after the initial reaction to CDA challenge was significantly greater (p less than 0.02) than after WMA challenge or after performance of nasal lavages without a challenge. The ability of CDA to induce a LPR strengthens the connection between initial mast-cell activation and the occurrence of a LPR.

Intranasal challenge of allergic subjects with the allergen to which they are sensitive rapidly produces sneezing, rhinorrhea, and airway obstruction. Nasal washings during the response reveal increased amounts of histamine, leukotrienes, prostaglandin D2 (PgD2), kinins and TAME-esterase in secretions. Although appearance of these mediators ceases shortly after challenge, many patients have a recrudescence of symptoms 3-11 h later, with a reappearance of the same mediators with the notable exception of PgD2. Subjects who respond to exposure to cold with rhinorrhea and nasal stuffiness were subjected to a 15-min nasal challenge with cold (-3-10 degrees C) dry (10% relative humidity) air and also responded with typical symptoms and the appearance of histamine, PgD2, TAME-esterase and leukotrienes. Nasal challenge with ragweed pollen by patients on immunotherapy showed that the threshold for response was greater and the amount of mediator found was less after treatment.

We have shown recently that kinins are generated during experimentally induced allergic rhinitis in man, and have demonstrated that substrates for kinin-forming enzymes are provided during the allergic response by a transudation of kininogens from plasma into nasal secretions. In light of this increased vascular permeability during the allergic reaction, we have extended our studies on the mechanisms of kinin formation to examine the potential involvement of plasma kallikrein. Allergic individuals (n = 7) and nonallergic controls (n = 7) were challenged intranasally with an allergen, and nasal lavages, obtained before and after challenge, were assayed for immunoreactive human plasma kallikrein/prekallikrein (iHPK). Post-challenge iHPK values were significantly elevated (p less than 0.01) in the allergic group (353 +/- 394 ng/ml; x +/- SD) as compared to the nonallergics (19 +/- 22 ng/ml), and correlated with increases in kinins, histamine, and N-alpha-tosyl-L-arginine methyl esterase (TAME-esterase) activity and with the onset of clinical symptoms. Gel filtration studies revealed that plasma prekallikrein is activated during the allergic response and contributes to kinin formation prior to interaction with plasma protease inhibitors. We also show that the majority of the TAME-esterase activity detected in nasal secretions during the allergic response is due to activities consistent with a plasma kallikrein/alpha 2-macroglobulin complex and with mast cell tryptase.

We have previously shown that both bradykinin and lysylbradykinin are generated in nasal secretions upon nasal challenge of allergic individuals with appropriate allergen and have suggested that these potent pro-inflammatory peptides may contribute to the pathogenesis of the allergic response. In this study we used a variety of synthetic substrates together with both thin layer and high performance liquid chromatography systems to examine the metabolism of these peptides in nasal secretions obtained by lavage. We now demonstrate that in addition to low levels of angiotensin-converting enzyme, nasal lavages contain an aminopeptidase activity that converts lysylbradykinin to bradykinin, and a carboxypeptidase that removes the C-terminal arginine from bradykinin and lysylbradykinin. The levels of all these activities are significantly increased after allergen challenge of allergic, but not nonallergic, individuals. The aminopeptidase and carboxypeptidase activities present in post-challenge lavages from allergic individuals convert lysylbradykinin to intermediate products (bradykinin and des (Arg10) lysylbradykinin) and eventually to des (Arg9) bradykinin. The nasal carboxypeptidase was activated 475% by 0.1 mM CoCl2 and was inhibited by the carboxypeptidase N inhibitor, MERGETPA (D-L-mercaptomethyl-3-guanidino-ethylthiopropanoic acid) (IC50 = 10 microM). The aminopeptidase activity was not affected by MERGETPA but was potently inhibited by amastatin and bestatin (IC50 = 0.05 microM and 3.0 microM, respectively). The activity of the aminopeptidase against its synthetic substrate was also inhibited by lysylbradykinin (IC50 = 50 microM). Both the carboxypeptidase and aminopeptidase activities had neutral pH optima and were inhibited by o-phenanthroline, but were unaffected by inhibitors of neutral endopeptidases (phosphoramidon) or angiotensin-converting enzyme (Captopril). The Km of bradykinin for the nasal carboxypeptidase was 139 +/- 14 microM (n = 3). We conclude that during the allergic response, nasal secretions contain aminopeptidase and carboxypeptidase activities that convert lysylbradykinin and bradykinin (B2 agonists) to des (Arg9) bradykinin (a B1 agonist). Because the nature of the kinin receptors in the nasal mucosa are currently unknown, it remains to be determined whether this metabolism results in the termination of biologic activity or the production of a biologically active moiety.

We have recently demonstrated that kinins are generated in vivo after nasal challenge with antigen of allergic, but not nonallergic, individuals. The present study was undertaken as a first step in determining the mechanism(s) of kinin formation during the allergic reaction and was directed towards establishing the availability and origin of kininogens in nasal secretions. Allergic individuals (n = 6) and nonallergic controls (n = 5) were challenged with antigen; and by using specific radioimmunoassays, nasal washes, obtained before and after challenge, were assayed for high molecular weight kininogen (HMWK), total kininogen (TK), albumin, and kinins. Dramatic increases in HMWK (1,730 +/- 510 ng/ml), TK (3,810 +/- 1035 ng/ml), kinin (9.46 +/- 1.75 ng/ml), and albumin (0.85 +/- 0.2 mg/ml) were observed after challenge of allergic individuals which correlated (P less than 0.001) with increases in histamine and N-alpha-tosyl-L-arginine methyl esterase activity and with the onset of clinical symptoms. For nonallergic individuals, levels of kininogens, albumin, and all mediators after antigen challenge were not different from base line. Linear regression analysis revealed excellent correlations (P less than 0.001 in each case) between increases in HMWK, TK, kinin, and albumin during antigen titration experiments and between the time courses of appearance and disappearance of HMWK, TK, kinin, and albumin after antigen challenge. Gel filtration revealed no evidence of degradation products of kininogens in nasal washes. For each allergic individual the ratio of HMWK/TK in postchallenge nasal washes was similar to the ratio of these two proteins in the same individual's plasma. These data suggest that, during the allergic reaction, there is an increase in vascular permeability and a transudation of kininogens from plasma into nasal secretions, where they can provide substrate for kinin-forming enzymes.

Allergic individuals and nonallergic controls were subjected to nasal challenge with allergen; and nasal washes, obtained before and after challenge, were assayed for high molecular weight kininogen (HMWK), total kininogen (TK), albumin and kinins. Following challenge of allergic individuals, HMWK, TK, kinin and albumin all increased dramatically, correlating (p less than 0.001) with the onset of clinical symptoms and with increases in histamine and TAME-esterase activity. No such increases were seen upon challenge of nonallergics. The time course of appearance and disappearance of the kininogens, kinins and albumin were all highly correlated (p less than 0.001 in each case) by linear regression analysis, as were the increases in kinin and each of the proteins during antigen titrations. For each individual, the plasma ratio of HMWK/TK was similar to the ratio of these two proteins in post-challenge nasal washes from the same individual. These findings are consistent with the hypothesis that, during the allergic reaction, vascular permeability increases, allowing a transudation of kininogens from plasma into nasal secretions, where they can provide substrate for kinin-forming enzymes.

Nasal lavage fluids from unstimulated individuals contain a histamine-releasing factor (HRF) similar to those which we have previously described from macrophages, platelets, and from blister fluids obtained during the late cutaneous reaction. The nasal HRF was partially purified by ion-exchange chromatography and gel filtration. Although some m.w. heterogeneity was observed, the majority of the HRF eluted at an apparent m.w. range of 15,000 to 30,000. This partially purified HRF induced histamine release from basophils of certain individuals. Histamine release occurred via a mechanism which is IgE-dependent in that: basophils desensitized by exposure to anti-IgE in the absence of calcium no longer respond to HRF, and desensitization with HRF reduces responsiveness to anti-IgE; and removal of IgE from the basophil surface by using lactic acid renders cells unresponsive to HRF. We have further defined this IgE dependence and have shown that the reason that only selected basophil donors respond to HRF is due to a previously unrecognized, functional heterogeneity of IgE. Thus, passive sensitization using sera from responders restored the responsiveness of acid-stripped basophils and conferred responsiveness to basophils of a nonresponder with naturally unoccupied IgE receptors. Sera from nonresponders failed to do this even though similar numbers of IgE molecules were put onto the basophil surface in each case. This property of responder sera was due to IgE because both heating sera at 56 degrees C for 2 hr and passage of sera over anti-IgE-Sepharose (which removes greater than 90% of the IgE) markedly reduced the ability of sera to induce responsiveness, and because an excess of either purified IgE myeloma or purified penicillin-specific IgE antibody from a nonresponder competitively inhibited the ability of IgE from responder sera to induce responsiveness to HRF. We conclude that nasal lavage fluids contain an HRF which induces basophil histamine release in a specific, IgE-dependent fashion but only from individuals with the appropriate type of IgE. Because we have shown that basophils are recruited into the nose during the late-phase reaction, we suggest that nasal HRF may induce these cells to release histamine and other mediators which could contribute to the symptomatology of the late-phase reaction.

The purpose of our study was to assess the effect of cold, dry air (CDA) on the nasal mucosa of selected individuals in relation to the release of inflammatory mediators associated with mast cells. 12 subjects with a history of nasal symptoms of rhinorrhea and congestion upon cold or dry environmental exposure were challenged by nasal breathing of CDA and warm, moist air (WMA). Each subject was tested on two occasions with the order of the challenges reversed. Symptom scores were recorded, and the levels of histamine, prostaglandin (PG) D2, kinins, and [3H]-N-alpha-tosyl-L-arginine methyl ester (TAME)-esterase activity in nasal lavage fluids were measured. CDA caused a significant increase in mediator levels and in symptom scores as compared to baseline or to WMA. No significant increase in symptom scores or mediators was noted after WMA challenge, with the exception of a marginal increase in kinins. The response to CDA was similar, regardless of challenge order. Changes in mediators correlated with one another, and symptom scores correlated significantly with the levels of histamine, kinins, and PGD2. Five subjects without a history of nasal symptoms on cold air exposure had no change in mediators or symptom scores after CDA or WMA challenge. We conclude that CDA causes the release of inflammatory mediators possibly associated with mast cells and speculate that such a mechanism may be involved in the bronchospasm induced by CDA in asthmatics.