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Research into the benefits of children eating breakfast has previously focused on educational and cognitive performance as well as behavior. Few nutritional investigations have utilized brain imaging technology in order to examine how breakfast influences brain function. This single case study used quantitative EEG (qEEG) in order to assess how three different breakfast choices affect a 12-year-old female’s brainwave activity. The three different breakfast conditions included no - breakfast, a high sugar/high carbohydrate breakfast , and a nutritionally balanced breakfast. The findings indicated that skipping breakfast significantly increased high beta activity associated with anxiety and focus issues. Eating a high sugar/high carbohydrate breakfast was also associated with increased high beta activity, but less significant than the no-breakfast option. Most importantly eating a nutritionally balanced breakfast was found to normalize the qEEG. The variation in high beta activity in the different breakfast options suggested that eating a nutritionally balanced breakfast may reduce anxiety and increase focus compared to skipping breakfast. These results may help explain why previous research has found cognitive, academic, and behavioral improvements when children consume breakfast. Furthermore, the qEEG should be considered in future nutritional studies as a measurement of brain function.

Many antiepileptic drugs (AEDs) have been tested on nonepileptic patients with a variety of diagnoses. The Food and Drug Administration has only approved certain AEDs for a small number of psychiatric conditions. There are few studies of nonepileptic patients that recommend an empirical trial of AEDs when isolated epileptiform discharges (IEDs) are identified in the electroencephalogram (EEG). However, no trials have been published. The purpose of this study is to evaluate the outcome of treating nonepileptic patients with AEDs when IEDs are present. Refractory cases were reviewed from a multidisciplinary practice whose EEG readings contained IEDs and were subsequently medicated with anticonvulsants by the clinic’s psychiatrist. The psychiatrist’s progress notes were assessed to determine the impact of adding anticonvulsants based on parent reports, teacher reports, and clinical observation. The final sample was composed of 76 refractory cases. Of the 76 patients treated with anticonvulsants, the majority were found to be improved in follow-up progress notes: 65 improved (85.53%), 6 unchanged (7.89%), and 5 more severe (6.58%). These observational findings suggest that further studies will be needed to show that IEDs may predict positive treatment outcome to anticonvulsant medication and act as a step toward an evidence-based treatment. Also, EEG screening may prove to be useful for refractory cases regardless of age, gender, or diagnosis.

Routine electroencephalograms (EEG) are not recommended as a screen for epileptic discharges (EDs) in current practice guidelines for children with autism spectrum disorder (ASD). However, a review of the research from the last three decades suggests that this practice should be reevaluated. The significant comorbidity between epilepsy and ASD, its shared biological pathways, risk for developmental regression, and cognitive challenges demand increased clinical investigation requiring a proactive approach. This review highlights and explains the need for screening EEGs for children with ASD. EEG would assist in differentiating EDs from core features of ASD and could be included in a comprehensive assessment. EEG also meets the demand for evidence-based precision medicine and focused care for the individual, especially when overlapping processes of development are present.

Pharmaco-electroencephalography (Pharmaco-EEG) studies using clinical EEG and quantitative EEG (qEEG) technologies have existed for more than 4 decades. This is a promising area that could improve psychotropic intervention using neurological data. One of the objectives in our clinical practice has been to collect EEG and quantitative EEG (qEEG) data. In the past 5 years, we have identified a subset of refractory cases (n = 386) found to contain commonalities of a small number of electrophysiological features in the following diagnostic categories: mood, anxiety, autistic spectrum, and attention deficit disorders, Four abnormalities were noted in the majority of medication failure cases and these abnormalities did not appear to significantly align with their diagnoses. Those were the following: encephalopathy, focal slowing, beta spindles, and transient discharges. To analyze the relationship noted, they were tested for association with the assigned diagnoses. Fisher’s exact test and binary logistics regression found very little (6%) association between particular EEG/qEEG abnormalities and diagnoses. Findings from studies of this type suggest that EEG/qEEG provides individualized understanding of pharmacotherapy failures and has the potential to improve medication selection.

Introduction Data from an EEG is not commonly used by psychiatrists to plan treatment and medication. However, EEG abnormalities such as isolated epileptiform discharges are found to be more prevalent in psychiatric patients, particularly those diagnosed with autism spectrum disorder (ASD). Most medications prescribed for ASD lower seizure threshold and increase side effects. Therefore, it may be prudent to order an EEG for ASD cases, especially those categorized as refractory. Methods The data set was obtained from a multidisciplinary practice that treats a wide variety of neuroatypical children and adolescent refractory patients. This study investigated 140 nonepileptic subjects diagnosed with ASD, aged 4 to 25 years. Visual inspection of the EEG was performed to search for paroxysmal, focal, or lateralizing patterns. Results Of the 140 subjects, the EEG data identified 36% with isolated epileptiform discharges. The χ analysis found no significant difference between genders among the three age groups. Findings indicated a high prevalence of isolated epileptiform discharges among individuals with ASD. Conclusions Our results find that compared with the healthy population, a large number of patients with ASD have isolated epileptiform discharges despite never having a seizure. Our findings support the use of EEG in children, adolescents, and young adults with ASD, regardless of gender or age. This is particularly true for those who exhibit aggressive behaviors or those who have failed previous medication attempts with stimulants, antidepressants, and/or antipsychotics.

Introduction. Twenty-eight anxious adults were assessed for frontal lobe alpha asymmetry, a brain state associated with depression and anxiety. Fifteen of the 28 exhibited significant asymmetry and 12 agreed to participate in a biofeedback program addressed at reducing frontal alpha asymmetry. Method. The program consisted of earlobe temperature biofeedback (ETB) and two forms of neurofeedback, alpha suppression and alpha symmetry training. Individuals were instructed to warm their right earlobe for six sessions, and half succeeded, though success was not required to advance to the next stage of training. For subsequent EEG training, two anterior sites were selected on the basis of poor alpha coherence. Individuals were trained to reduce alpha magnitude at these sites by 10% for 30 min or more, which took from 6 to 16 sessions to achieve. Once successful with alpha suppression, individuals were trained to improve alpha symmetry between the sites by 15% for 30 min or more. Results. This feat took ...

Current approaches to QEEG-guided neurofeedback involve efforts to normalize the abnormalities seen, without reference to the functional localization of the cortical areas involved. Recent advances in cortical neurophysiology indicate that specific brain areas are developed to perform certain functions (cortical modules). Complex brain functions require cooperation between modules, particularly during a learning situation. For example, the left prefrontal “activation module” must cooperate with one or both occipital “visual modules” to attend and see something on a chalkboard. To remember what has been seen, both temporal “memory modules” must cooperate with the visual modules for the image to be retained in short-term memory. If the connections between these modules are not functioning optimally, visual learning will be impaired. Decreased coherence (hypocoherence) indicates a decrease in functional connectivity between these modules, and increased coherence (hypercoherence) indicates an increas...

In psychiatry, the reliability of diagnosis (a symptom-based approach) is instrumental in the management of medications and treatments. The National Institute of Mental Health (NIMH) is now searching for neurobiological measures that account for observed and reported symptoms. The results of our study of 386 refractory clinical cases suggest there are four neurobiological measures that account for medication failure: encephalopathy, focal slowing, beta spindles and transient discharges. One or more of these neurobiological measures (neurobiomarkers) explained why medication failed in each of these refractory cases. Our investigation found positive correlations between numbers of medications being prescribed and numbers of neurobiomarkers being identified in children and adolescents. In adults we also we found a positive correlation between numbers of medications being prescribed and number of diagnoses. This study represents a model that could improve the efficacy of the psychotropic intervention and treatment selection in refractory psychiatric cases.

Intentional enhancement of regional cerebral blood oxygenation (rCBO2) in specific cerebral locations was studied as a brain exercise. A review of literature showed the effect of brain exercise on brain physiology. Hemoencephalography (HEG), a graphic analog of brain blood flow of oxygenated hemoglobin indicated by non-invasive infrared spectroscopy, was used to guide intentionally increasing rCBO2. A musical note and visual graphic keyed to changes in cortical blood oxygenation was provided to the participant. A primary aim of this study was to demonstrate the capacity of subjects with brain disorders to increase oxygenation of selected brain tissue using HEG and test the hypothesis that multiple repetitions of these brain exercises improved sustained attention measured with a continuous performance test. The impulsivity score for subjects in the exercise group was in the normal range after 10 sessions. In a small set of subjects, low arousal SPECT images showed increased vascularity after 30 half-hour sessions of intentional enhancement of local blood oxygenation.

In hypothalamic cells cultured in serum-free medium, the quantity of tyrosine hydroxylase mRNA increases after treatment with an activator of the protein kinase A pathway (8-bromoadenosine cyclic AMP, 3-isobutyl-1-methylxanthine, or forskolin) or an activator of protein kinase C (12-O-tetradecanoylphorbol 13-acetate or sn-1,2-diacylglycerol). The tyrosine hydroxylase mRNA level decreases in the cells after inhibition of protein kinase C with calphostin C or after depletion of protein kinase C by extended phorbol ester treatment. These data suggest that both protein kinase pathways regulate tyrosine hydroxylase gene expression in hypothalamic cells. As simultaneous activation of both pathways has less than an additive effect on the tyrosine hydroxylase mRNA level, they appear to be interrelated. Compared with the rapid and dramatic increase of the tyrosine hydroxylase mRNA level in pheochromocytoma cells, activation of the protein kinase A or protein kinase C pathway in the cultured hypothalamic cells induces slow changes of a small magnitude in the amount of tyrosine hydroxylase mRNA. The slow regulation of tyrosine hydroxylase gene expression in hypothalamic dopaminergic neurons corresponds to the relatively high stability of tyrosine hydroxylase mRNA (half-life = 14 +/- 1 h) in these cells.

It is well known that deficit of endorphins plays an important role in disturbances of human psycho-physiological status. Previously, we revealed that brain endorphinergic structures have quasiresonance characteristics. On the basis of these data, a method of activation of the brain endorphinergic structures by means of noninvasive and rather selective transcranial electrostimulation (TES) as a kind of functional electrical stimulation (FES) was elaborated. New models of TES devices (TRANSAIR) were developed for indoor and outdoor usage. To increase the efficacy of TES, the frequency modulation according to normal distribution in the limits of the quasiresonance characteristics was put into operation. The blind and placebo-controlled (passive and active placebo) study was produced to estimate the TES effects on stress events and accompanied psycho-physiological and autonomic disturbances of different intensities on volunteers and patients in the following groups: everyday stress and fatigue; stress in regular military service and in field conditions; stress in the relatives of those lost in mass disaster; posttraumatic stress (thermal burns); and affective disorders in a postabstinence period. Some subjective verbal and nonverbal tests and objective tests (including heart rate variability) were used for estimation of the initial level of psycho-physiological status, which changes after TES sessions. It was demonstrated that fatigue, stress, and other accompanied psycho-physiological disturbances were significantly improved or abolished after 2-5 TES sessions. The TES effects were more pronounced in cases of heavier disturbances. In conclusion, activation of the brain endorphinergic structures by TES is an effective homeostatic method of FES that sufficiently improves quality of life.

The hypothalamus plays a central role in the integrated control of feeding and energy homeostasis. We have identified two novel neuropeptides, both derived from the same precursor by proteolytic processing, that bind and activate two closely related (previously) orphan G protein-coupled receptors. These peptides, termed orexin-A and -B, have no significant structural similarities to known families of regulatory peptides. prepro-orexin mRNA and immunoreactive orexin-A are localized in neurons within and around the lateral and posterior hypothalamus in the adult rat brain. When administered centrally to rats, these peptides stimulate food consumption. prepro-orexin mRNA level is up-regulated upon fasting, suggesting a physiological role for the peptides as mediators in the central feedback mechanism that regulates feeding behavior.

The relationship between leucine5-enkephalin-containing nerve terminals and midbrain dopaminergic neurons was studied in the adult rat by light and electron microscopy. For light microscopy, alternate midbrain sections were immunostained with rabbit polyclonal antibodies against leucine5-enkephalin and tyrosine hydroxylase, by means of the peroxidase antiperoxidase technique. Leucine5-enkephalin stained fibers and terminals were observed with varying density in the retrorubral field (dopaminergic nucleus A8 region), substantia nigra pars compacta (dopaminergic nucleus A9 region), and ventral tegmental area and related nuclei (dopaminergic nucleus A10 region). For electron microscopy, midbrain sections were immunostained with a mouse monoclonal antibody against leucine5-enkephalin and a rabbit polyclonal antibody against tyrosine hydroxylase, by means of the peroxidase antiperoxidase technique and silver-intensified colloidal gold reactions, respectively. The nucleus A10 area was examined at the electron microscopic level, and there were a) both symmetric (75%) and asymmetric (25%) synapses made between leucine5-enkephalin axon terminals and dopaminergic dendrites, and also synaptic contacts with unlabeled dendrites; b) leucine5-enkephalin synaptic contacts with dopaminergic dendrites that were covered with astrocytic membranes; and c) leucine5-enkephalin appositions with unlabeled nerve terminals that made synaptic contacts with dopaminergic dendrites, suggestive of axo-axonic connections. These findings provide the structural basis for both direct and indirect control of A10 dopaminergic neurons by enkephalin-containing nerve terminals.

Single- and double-labeling immunocytochemical staining procedures were used to examine the relationship between adrenocorticotropin (ACTH)-containing nerve terminals and dopaminergic (DA) neurons in the rat midbrain, using both light and electron microscopy. At the light microscopic level, ACTH neuronal processes were found largely in restricted regions occupied by the mesolimbic and mesocortical DA neurons. At the electron microscopic level, in the central linear nucleus, ACTH axon terminals made symmetric and asymmetric synaptic contacts with DA dendrites, as well as appositions with unlabeled axon terminals which, in turn, synapsed upon DA dendrites. These data suggest that ACTH functions as a neurotransmitter/neuromodulator in the brain, and such ACTH-DA synapses may be important for stress-induced changes in mesocorticolimbic DA neuronal activity.

We investigated the involvement of second messenger systems in the control by pituitary cytotropic factor (CTF) of tyrosine hydroxylase (TH) expression in primary cultures of hypothalamic cells. Forskolin, an activator of adenylyl cyclase, as well as Sp-cAMP[S] [(Sp)-cyclic adenosine 3',5'-monophosphothioate], a cAMP agonist, and theophylline, an inhibitor of phosphodiesterase activity, stimulate the secretion of dihydroxyphenylalanine (DOPA) and dopamine (DA), suggesting a role for cAMP-dependent protein kinase in the secretion of catecholamines by hypothalamic dopaminergic cells. When cells were cultured with either CTF or forskolin for 14 days, a progressive increase in the secretion of DOPA and DA was observed throughout the period of incubation. At the end of the 2-week culture period, the amount of TH in the cells, determined by immunoblot analysis, was appreciably increased compared to controls. When the cells were analyzed immunocytochemically for TH, the TH-positive cells that had been incubated with CTF or forskolin for 2 weeks were found to have neurites that appeared larger than those of TH-positive cells in the controls. The diameters of the perikarya of TH-positive cells in cultures incubated with CTF also appeared larger than the controls. After incubation of hypothalamic cells with CTF for 96 h, the amount of TH mRNA in the cultures was significantly increased. When membranes isolated from PC12 cells were incubated for 10 min with 50 microM forskolin, the specific activity of adenylyl cyclase was increased 20-fold; CTF had no effect on adenylyl cyclase activity of PC12 cell membranes. Yet, CTF significantly (P less than 0.001) stimulated the secretion of DOPA and DA by PC12 cells. When hypothalamic cells were incubated with both forskolin and CTF, using doses of each that stimulated maximal secretion, the secretion of DOPA and DA was equal to sum of the secretions with each stimulant alone. These additive actions of forskolin and CTF and the failure of CTF to activate adenylyl cyclase in membranes of PC12 cells suggest that forskolin and CTF stimulate catecholamine secretion by hypothalamic dopaminergic cells through different mechanisms, perhaps through different protein kinases. When hypothalamic cells were incubated with CTF and W-7 [N-(6-aminohexyl)5-chloro-1-naphthalenesulfonamide], an inhibitor of calmodulin, the secretion of DOPA was significantly (P less than 0.001) less than that in cultures that were not incubated with W-7. The findings of this study suggest that TH expression in hypothalamic dopaminergic cells is controlled by redundant protein kinases, including cAMP-dependent protein kinase and Ca2+/calmodulin-dependent protein kinase.

With electroencephalographic (EEG) biofeedback (or neurofeedback), it is possible to train the brain to de-emphasize rhythms that lead to generation and propagation of seizure and emphasize rhythms that make seizures less likely to occur. With recent improvements in quantitative EEG measurement and improved neurofeedback protocols, it has become possible in clinical practice to eliminate seizures or reduce the amount of medication required to control them. In this article, the history of neurofeedback for epilepsy is presented followed by discussions of the relevant neurophysiology of epilepsy. A model of how neurofeedback might raise the seizure threshold is then presented. Clinical experience using a quantitative EEG-guided approach is described, including a representative case study.

Rostral ventrolateral medulla (rVLM) and parapyramidal region (PPr) serve as important medullary control sites for sympathoexcitation. rVLM and PPr have direct projections to the intermediolateral cell column (IML) that are thought to be important in maintaining mean arterial blood pressure (MAP). Substance P (SP) is found in PPr neurons and in and near the subretrofacial area of the rVLM. At least some of these cells project to the IML. We investigated the involvement of SP at the IML in mediating rVLM- and PPr-evoked pressor responses in the chloralose-anesthetized cat. Pressor responses to electrical and chemical PPr and rVLM stimulation were altered after intrathecal injection, at the level of the T1-T3 spinal cord, of either SP antagonist [d-Pro2,d-Phe7,d-Trp9]-SP, SP antagonist CP 96,345, or SP antiserum. Although MAP and heart rate responses to PPr stimulation were attenuated by intrathecal SP antagonists or antiserum, MAP responses to rVLM stimulation were augmented. Previous studies have revealed differences in transmitters associated with these two areas, even though the general response of both areas is sympathoexcitatory. The present study implies that the identical substance may increase or decrease the MAP response depending on the pathway activated.

To evaluate the significance of endogenous vasopressin and oxytocin in control of anterior pituitary hormone release, antiserum against vasopressin (AB-VP) or oxytocin (AB-OT) were microinjected into the third ventricle (3V) of conscious, ovariectomized rats to immunoneutralize endogenous VP or OT, respectively. Blood samples were collected just before and at different times after the microinjections. There were no differences in the plasma LH, FSH, PRL and TSH concentrations between control groups injected into the 3V with normal rabbit serum (NRS) and groups submitted to the intraventricular injection of AB-OT or AB-VP for 24 h after the injections. Plasma growth hormone (GH) declined significantly by 4 h after NRS injection, remained low at 6 h and had rebounded to nearly initial levels at 24 h. This pattern was not changed by microinjection of AB-VP, but plasma GH increased significantly compared to initial values in the period from 1 to 24 h after intraventricular microinjection of AB-OT. The intraventricular injection of AB-VP or AB-OT significantly decreased plasma ACTH; however, the effect of AB-VP was more prolonged and persisted for 6 rather than 4 h after injection. Thus, endogenous oxytocin may play a role in the control of basal GH release probably by stimulating somatostatin secretion and/or inhibiting GH-releasing hormone secretion or by both actions. On the other hand, both endogenous vasopressin and oxytocin play a physiologically significant stimulatory role in the control of basal ACTH release.

Estrogen formation is catalyzed by the aromatase cytochrome P450 (P450AROM) enzyme. Aromatase activity has been detected in several regions in the rat brain. In the present study, we used peptide-generated polyclonal antibodies raised against a 20-amino acid synthetic fragment of the rat P450AROM protein (as deduced from the nucleic acid sequence of the rat P450AROM complementary DNA), to determine the location of this enzyme in rat brain sections. Immunoreactive antisera were titered by means of an enzyme-linked immunosorbent assay and purified by diethylaminoethyl-Affigel Blue chromatography. Specific immunoreactivity was confirmed by Western blot analysis using known aromatase-containing tissue (rat ovary homogenates and microsomal fractions). Evaluation of the distribution of P450AROM immunoreactivity in brain sections of male and female rats (30 and 60 days of age) was performed using the avidin biotin peroxidase immunocytochemical technique and light microscopy. P450AROM immunoreactivity appeared to be localized to neurons, and was present in brain regions and nuclei where enzymatic activity has been reported. For example, intense immunoreactivity was observed in the amygdaloid structures and supraoptic nucleus, whereas moderate to light immunoreactivity was evident in the paraventricular and arcuate nuclei and hippocampus. Surprisingly, neurons in the bed nucleus stria terminalis, medial basal hypothalamic, and preoptic areas displayed little aromatase immunoreactivity. However, P450AROM immunoreactivity was detected in specific brain regions not previously recognized to contain the enzyme (i.e. intense staining was seen in the reticular thalamic nucleus, olfactory tract and piriform cortex, as well as other brain structures). The pattern, distribution, and intensity of P450AROM immunoreactivity was similar regardless of sex or age. In this study, microsomal preparations derived from a new brain area (i.e. the reticular thalamic nucleus; Rt) displaying P450AROM immunoreactivity were observed to contain detectable levels of aromatase enzymatic activity, as determined by the 3H2O-release assay. The activity in the Rt was inhibited by a known aromatase inhibitor, 4-hydroxyandrostenedione. These results confirm histologically the localization of P450AROM to brain regions where aromatase enzymatic activity has been detected and extend the knowledge of its location to areas previously unknown as sites of aromatase activity, which may be involved in the modulation of neuroendocrine function and reproductive behavior.

The burgeoning field of neuroimmunology currently emphasizes a brain-immune link represented by hormones, neurotransmitters, neuropeptides, cytokines (1) and other substances of the CNS which are shared in common with the immune system and can act either directly or indirectly on components of the immune system or their target tissues. This concept essentially depicts the CNS as having an efferent outflow of active principles to a variety of peripheral structures. Another concept of potential importance in the maintenance of a homeostatic brain-immune interaction is that of immunoneurology, whereby principles derived from peripheral sources feed back onto the CNS. In this sense, immune cells, their products and other related substances can be transported from their source via the blood stream to the CNS wherein they may access the internal milieu and can, therefore, be considered afferent to the CNS. This review describes studies on transport of immunogammaglobulins (IgG) and albumins into the CNS of rat, rabbit and guinea pig using several techniques: immunocytochemistry (ICC), colchicine administration, active immunization, induced experimental allergic encephalomyelitis (EAE), radioisotope labeling, enzyme-linked immunosorbent assay (ELISA), rocket Immunoelectrophoresis and an in situ vascular brain perfusion method. Results from these studies reveal that serum albumin and globulin can enter the brain via several routes including that of active neuronal uptake by nerve endings, and subsequent transport to their cell bodies of origin via retrograde transport. These compounds may also enter the brain at circumventricular regions wherein functional leaks occur. Finally, there appears to be a saturable transport mechanism for IgG that is used to traverse the blood-brain barrier (BBB) and gain direct entry into the CNS.

A technique for implanting an intragastric cannula in the rat is described along with the usefulness of this technique for the periodic administration of ethanol (ETOH). Our results indicate that rats receiving ETOH (3.0 g/kg) every eight hours for three days exhibit approximately a 37% (p less than 0.05) depression in serum luteinizing hormone (LH) levels, with approximately a 40% (p less than 0.025) increase in serum prolactin (Prl) levels when compared with rats receiving saline only. These results are similar to those acute effects observed following multiple IP administration of ETOH; however, the intragastric route of delivery provides an animal model for studying the effects of ETOH on the hypothalamo-hypophysial-unit with only a minimum amount of stress to the animal. Advantages of this technique are discussed in comparison with other methods of ETOH administration and their effects on the hypothalamic-LH axis.

It is difficult to reconcile the relative absence of evidence available on hormone pathways of the CSF and the ventricular route hypothesis, even when only very particular hormone systems are examined. One must consider several of the parameters such as possible entry of hormones into the CSF via the choroid plexus, CVOs and intraventricular nerve endings, or even the possibility that they may cross the blood-brain barrier. These considerations are important for whatever hormone system is being studied, and there probably may turn out to be several pathways for any particular hormone to access the CSF. Despite the fact that there are many acceptable features of the ventricular route hypothesis, more investigation remains to be undertaken in order to fully appreciate the importance of the CSF as an integrator of neuronal and endocrine function.

Vascular permeability was examined in fetal neocortical transplants grafted into the cerebral cortex of newborn rats. Methods based on the histochemical labeling of intravenously administered horseradish peroxidase or on the immunocytochemical demonstration of endogenous immunoglobulin showed the presence of a blood barrier within the transplants.

We previously reported that subarachnoid injection of a peptide antagonist to substance P attenuated by half the reflex pressor response to static muscular contraction. Subsequently, some of the peptide antagonists to substance P have been found to possess local anesthetic effects. Therefore, we have repeated our experiments using a substance P antiserum, which was shown to be without local anesthetic effect. We found that intrathecal injection of the antiserum attenuated by more than half the reflex pressor response to static contraction of the triceps surae muscles of cats.

An intact blood–brain barrier (BBB) is a prerequisite to maintaining functional compartmentalization between the neural and immune systems. Only small amounts of immunoglobulins access the internal milieu of the brain, probably via so-called “functional leaks” existing in the region of the circumventricular organs. However, with aging and disease, globular and other proteins can be found within the cerebrospinal fluid (CSF) because of disruption of perhaps both the BBB and the blood–CSF barrier. There is an increase of lgG, IgA, albumin, and prealbumin in CSF of patients with Alzheimerapos;s disease. The presence of these proteins is taken to be pathognomonic for neuronal impairment, and they are believed to be associated with the amyloid deposits of senile plaques. Our studies have shown that albumins may occur naturally in some CNS neurons. Immunocytochemical studies with antibodies to rat serum albumin have shown the uptake of this serum protein by nerve endings with retrograde transport to perikarya of their cells of origin. Likewise, we have also shown than an endogenous albuminoid substance occurs in arcuate nucleus neurons of the hypothalamus that immunoreact with antibodies to bovine serum albumin. The arcuate nucleus neurons are neurosecretory and have neurohemal endings in contact with blood vessels of the hypothalamohypophysial vasculature. These neurohemal contacts are capable of taking up albumins from the blood for retrograde transport. We, therefore, hypothesize that immunoglobulins may be similarly incorporated by neurons having neurohemal contacts and access the CNS in this and several other ways. We have localized endogenous gammaglobulins in brains of both immunized and nonimmunized rabbits with antisera against rabbit lgG generated in sheep, goat, and mouse. However, serum proteins are also found in neurons without neurohemal contacts. Taken together, albumins, globulins, and other substances may reach the interior milieu of the CNS via: (1) endothelial transcytosis, (2) neurohemal contacts whereby neurons take up blood-borne substances and retrogradely transport them to their perikarya, (3) circumventricular organs (inter- and intraependymal transport), (4) functional leaks at the interface of the circumventricular organs and the brain, (5) a nose–brain pathway, (6) a meningeal pathway, and (7) transsynaptic transport, i.e., substances passed from a neurohemal cell to other connecting neurons.

Nerve fibers containing substance P (SP) were localized in ovaries from juvenile and peripubertal rats by immunofluorescence. These fibers were closely associated with the theca externa of antral follicles, as well as being in the interstitial tissue and within the tunica adventitia of small blood vessels, mostly arterioles. Consistently, the greatest amount of SP immunoreactivity was observed surrounding the ovarian vasculature. Substance P was not detected in cells or within the corpora lutea (CL). Additionally, the peripubertal animals seemed to have a greater concentration of ovarian SP than the juvenile animals. Possible functional roles for this peptide in the ovary are discussed.

The tyrosine hydroxylase (TH)- and phenylethanolamine N-methyltransferase (PNMT)-immunoreactive cells of the medulla are closely associated with cardiovascular control in both the cat and rat. Although it is often the species of choice for cardiovascular studies, no previous study had characterized these cell groups in the dog. The TH- and PNMT-immunoreactive cells of the dog were distributed much as they are in both cat and rat but with some species variations, which may be indicative of their functional role.

Localization studies of the hypothalamohypophysial and tuberoinfundibular neurosecretory systems were performed in the adult male mallard duck with an immunoperoxidase techinque for the demonstration of neurophysin (NP) and gonado-tropin-releasing hormone (Gn-RH) and with aldehyde fuchsin for the staining of neuosecretory material (NSM). A comparison was made between the distribution of NSM stained with aldehyde fuchsin and NP seen by immunocytochemistry. The magnocellular perikarya of the supraoptic (SON) and paraventricular (PVN) nuclei, the zona externa of the anterior median eminence (ME), the fiber layer of both the anterior and posterior ME, and small neurons in the tractus quintofrontalis were stained by both the immunoperoxidase method for NP and by the aldehyde fuchsin stain. In contrast, the parvocellular neurons of the PVN, extra-hypothalamic neurosecretory fibers dorsal to the anterior commissure in the septal region and tanycytes lining the ventral 1/3 of the third ventricle at the level of the anterior ME, were stained only by the immunocytochemical procedure for NP. These observations indicate that immunocytochemistry is more sensitive than aldehyde fuchsin staining for detecting low concentrations of NP in cells and tissues, but the two techniques produce comparable results where the concentration of the NP is relatively high. Two populations of beaded axons containing Gn-RH were distributed throughout the zone externa of both the anterior and posterior ME. One group of fibers paralleled the hypothalamo-hypophysial neurosecretory tract whereas the other was distributed in the contact zone of the ME. Immunoreactive Gn-RH was found in the cytoplasm of a sparse population of cell bodies in the dorsolateral portion of the arcuate nucleus as well as in the axons that project from this nucleus ventrally towards the ME.

Scanning electron microscopy was used to assess the ultrastructural differences exhibited by the varigated ependymal lining of the near-term human fetal 4th ventricle. The central portion of the fourth ventricular floor, including the median sulcus is punctuated by numerous clumps of cilia. The density of cilia here is not as great as that described for other regions of the human cerebral ventricular system; accordingly, underlying substructure can be noted. There are distinct differences between ependymas that line the floor of the fourth ventricle with those of the adjacent area postrema. The latter region possesses not cilia, but instead exhibits a dense knap of microvilli. The ultra-architecture of the choroid plexus is relatively similar to that of other circumventricular organs with the exception that it possesses small isolated groups of cilia as well as microvilli. These findings are discussed with respect to the dynamics of local CSF movement and flow, ependymoabsorption and ependymosecretion

Light and electron microsopic examination of choroid plexuses from lateral ventricles of water-deprived and subcutaneously or intravenously vasopressin administered rats reveal morphologic changes typical for vasopressin responsive fluid transporting epithelia during hormonal stimulation. Ultrastructural changes noted in both dehydrated and vasopressin treated animals included: the frequent occurrence of choroidal "dark" cells, dilatation of the lateral and basal intercellular spaces, increased vacuolization of the apical cytoplasm, and a change in microvillar conformation from the normal clavate type to those with a filiforma shape. On the basis of the ultrastructural changes observed it is proposed that the choroids plexus be regarded as a target tissue for vasopressin. These findings indicated that a vasopressin mediated transchoroidal cerebrospinal fluid absorption capability exists.

Antisera to luteinizing hormone-releasing hormone (LHRH) generated against hapten-conjugates in which BSA (bovine serum albumin) is used as a carrier can contain both anti-LHRH and anti-BSA antibodies. Such antisera can cause the false-positive staining of neuronal cell bodies and other elements of the medial basal hypothalamus owing to the presence of anti-BSA, which cross-reacts with albuminoid substances within these cells. Differential blocking experiments using either BSA or LHRH or both BSA and LHRH as immunoabsorbents demonstrated that recent reports of LHRH-containing neurons in the medial basal hypothalamus of the rat have arisen from false-positive results due to the presence of anti-BSA within the anti-LHRH antisera used. Immunocytochemical evidence of LHRH-containing cell bodies in the medial basal hypothalamus (especially within the arcuate nucleus) of the rat remains unproven.

These prescient words expressed by the late Sir Francis KNOWLES in his introduction to the last International Symposium on Neurosecretion both remind and foretell that the concept of neurosecretory neurons as predominantly residing within the hypothalamohypophyseal pathway should be expanded to include an extensive system of neurosecretory fibers involved in numerous brain functions.

Light- and electron-microscopic immunocytochemistry (LM-ICC and EM-ICC) were used to visualize luteinizing hormone-releasing hormone (LHRH) in fibres associated with ventricular ependyma and tanycytes of the median eminence. LM-ICC suggests that LHRH fibers appear to enter the third ventricle. However, with EM-ICC, LHRH fibers are in fact found within ependymal canaliculi formed by adjacent ependymal cells. The canaliculi contain other myelinated and unmyelinated axons in addition to immunoreactive LHRH fibers. Thin slips of ependymal and tanycyte processes project into the canaliculi and enclose axons to varying degrees. At the median eminence many LHRH fibers bend sharply downwards from their ventricular course and travel with tanycytic processes towards their common destination - the perivascular space of the hypophysial-portal vascular system. Here, EM-ICC reveals that LHRH fibers closely contact basal processes of tanycytes. Lateral processes from tanycytes form glioplasmic sheaths which surround some individual LHRH fibers. A few LHRH terminals contact the perivascular space directly but more often are separated from the perivascular space by intervening glia. It is hypothesized that: (1) glia of this region responds to the physiological state of the animal and may determine the degree of LHRH secretion by varying the extent of glial investment of LHRH terminals; and (2) may play a role during development by providing direction and support for LHRH fibers similar to that described for radial and other glial cells.

These studies were designed to determine the effects of castration and ethanol (ETOH) on the relative content of substance P (SP) immunoreactivity in the hypothalamus and the central and medial amygdaloid nuclei (CM-AM). Differences visualized immunocytochemically between saline-treated intact and castrated rats indicated that a visible decrease in the number and intensity of immunostained fibers within the CM-AM occurred following castration. Conversely, the number of labeled fibers and the intensity of the reaction product was greater in castrated rats treated with ETOH as compared to the castrated rats receiving only saline. In ETOH-treated intact animals, the number of SP-containing fibers of the CM-AM was slightly greater than the saline-treated intact controls. Similar results were seen for specific regions of the hypothalamus although they were less pronounced than that visualized in the CM-AM. These data indicate that both castration and administration of ETOH affects hypothalamic and amygdaloid content of SP, and also suggests that ETOH may diminish the release of SP. Possible interactions between SP and luteinizing hormone-releasing hormone are discussed.

The central effects of both an antagonist and an antiserum to substance P (SP) on gonadotropin and prolactin (Prl) secretion were studied in castrated male rats. The lateral ventricular injection (20μg) of an analogue to SP possessing antagonistic properties resulted in significantly suppressed serum LH levels without altering serum FSH and Prl levels when compared with saline-injected control animals. Similarly, the lateral ventricular injection of an antiserum to SP also resulted in significantly suppressed LH levels when compared to control animals injected with normal rabbit serum. Additionally, no changes were observed in the levels of serum FSH and Prl as a result of the anti-SP injection. Thus, although indirect, these results support the hypothesis that SP may have a central stimulatory action on LH secretion, but not FSH and Prl secretion.

3H-corticoids were localized by autoradiography in small neurons in the area of the magnocellular paraventricular nucleus of mallard ducks. Correlative data show that: (1) the label is principally unmetabolized steroid, (2) the hypothalamus competitively binds corticosterone, (3) the paraventricular nucleus contains immunoreactive neurophysin, is richly innervated by boutons of monoaminergic nerves and is involved in the adaptive response to osmotic stress.

This study utilized the preembedding immunocytochemical technique in order to identify LHRH-containing neurons in rat brain and define their ultrastructural characteristics. LHRH-containing neurons in the vertical limb of the diagonal band of Broca, medial septum, triangular nucleus of the septum and other regions were studied by taking ultrathin serial sections. These neurons had scant cytoplasm surrounding a centrally-located, spheroid, euchromatic nucleus. Neurosecretory granules were evenly distributed throughout the cell, but many tended to lie directly under the plasmalemma. The cytoplasm was organized in such a way that the most extensive portion of the rough endoplasmic reticulum was polar opposite to areas having high concentrations of Golgi complex, lysosome-like bodies, smooth endoplasmic reticulum and ribosomes. The perikarya had no axosomatic synapses but functional interaction via unspecialized appositions to the plasmalemma cannot be discounted. Many of the perikarya bore at least one cilium. Processes from immunonegative cells were occasionally observed to penetrate the cytoplasm of the LHRH perikaryon or its processes. At their points of origin, dendrites were found to be broadened processes containing many elements common to the cytoplasm: ribosomes, smooth endoplasmic reticulum, cristal and lamellar mitochondria, neurotubules, and an occasional alveolate caveola. Infrequently, some of the LHRH axons were partially myelinated. This method of studying serial-sectioned immunocytochemically-identified cells is suggested as a means of describing the cellular and subcellular characteristics of other specific peptide-containing cells.

Ethanol (ETOH) has been shown to have pronounced effects on reproductive endocrinology in humans as well as laboratory animals. We have studied the effects of ETOH on the hypothalamic-pituitary-luteinizing hormone (LH) axis, using the male rat as an animal model. In order to better understand the method by which ETOH depresses plasma LH levels, we have used both quantitative and qualitative methods to analyze the effects of ETOH on hypothalamic luteinizing hormone-releasing hormone (LHRH). As measured by RIA, both saline and ETOH-treated rats showed a decrease in hypothalamic LHRH content with a concomitant increase in plasma LH; however, the animals treated with ETOH retained significantly greater concentrations of LHRH and showed significantly lower plasma LH levels when compared to saline-treated controls. In addition, ETOH-treated intact animals showed significant increases in LHRH content, with LH levels remaining significantly lower than the saline-treated intact controls. Immunocytochemical assessment of the relative content of LHRH within each group concurred with the results obtained using RIA. These data as well as other data obtained from other laboratories indicate that alcohol-induced decreases in LH levels are due to a diminished release rate of hypothalamic LHRH.

Light and electron microscopic autoradiographic analysis of the medial basal hypothalamus of rat brains incubated for 30 and 60 minutes in tritiated luteinizing releasing factor (3H-LRF) revealed selective uptake in the form of silver grains over specialized ependyma (tanycytes) and perivascular glial cells in the palisade-contact zone of the median eminence. The functional capacity of tanycytes and glia are discussed in light of these data.

The ultrastructure of the normal median eminence of the male rhesus monkey (Macaca mulatta) is described using high-voltage electron microscopy. Surface specializations of ependymal cells lining the infundibular recess included cilia, apical extrusions, and microvilli. Supraependymal cells were predominantly macrophage-like, but examples of lymphocytic types were also seen. Tanycytes had long, branching, basal processes filled with numerous microtubules, some lipid droplets, and granules. The zona interna was composed of large unmyelinated neurosecretory fibers. A few myelinated fibers were also seen, but their character as neurosecretory fibers could not be established. The zona externa was composed of densely-packed profiles of neuro secretory fibers of small diameter, was well-vascularized and contained the terminations of tanycytes. Perivascular glial cells, vesiculated elements, pituicytes, and cellular elements common to connective tissue were observed. The intricate relationships between both the cellular and fibrous elements of the median eminence can be appreciated with the capability of high-voltage electron microscopy to discern ultrastructure in sections 10 times thicker than those used for low-voltage electron microscopy. The median eminence of this primate species has an ultrastructural organization similar to that described for most other species.

The effects of subcutaneous injections of vasopressin on the passive avoidance behavior of rats were investigated in an extensive study. 200 male Wistar rats were tested in a step-through passive avoidance task. The animals were assigned randomly to 1 of 20 experimental groups consisting of five vasopressin injection and four shock level conditions. Each animal was trained to enter a dark compartment, then subjected to 0.25, 0.10, 0.05 mA or no foot shock for 2 sec. 60 min prior to a retention test administered 24 h after the foot shock, each animal was given a single injection of 0.30, 0.12, 0.06, or 0.03 IU of vasopressin or of saline. Time to reenter the shock compartment was tested 24 and 48 h after the foot shock. Latencies in both retention tests indicated that, although there was a significant effect of shock level on latency scores, there was no effect of vasopressin with any dose level tested. The inability to find an effect of vasopressin in this study is contrary to results of other studies. Several factors, including general reactivity of the animals or the distribution system for vasopressin in the brain, might provide the underlying reason for these dramatic differences.

Localization of neurophysin in neurons of the supraoptic nucleus was accomplished using an unlabeled-antibody, post-embedding, immunoperoxidase technique. Neurophysin was exclusively associated with neurosecretory granules within cell bodies of supraoptic neurons and their processes.