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BackgroundDeteriorated quality of life (QOL) is a major problem in osteoporotic women. However, little is known regarding the determinants of QOL in patients with osteoporosis.ObjectiveOur aim was to explore the role of vitamin D status on QOL score in osteoporosis with high fracture risk.MethodsPatients were osteoporotic women aged ≥70 years and with ≥1 risk factor for incident fracture, namely prevalent osteoporotic fracture, bone mineral density (BMD) >–3.0 SD of young adult mean, or high bone turnover marker. Health-related QOL was assessed using the Japanese Osteoporosis Quality of Life Questionnaire (JOQOL). When patients were classified into quartiles by total QOL score). Serum 25-hydroxyvitamin D (25[OH]D) level was measured by immunoassay.ResultsA total of 1585 osteoporotic women were included in the study (age range, 70–95 years). Age, body mass index, serum 25(OH)D status (low, normal, or high), bone mineral density, number of prevalent vertebral fractures, presence of hypertension, presence of osteoarthritis, and history of falls were significantly correlated with QOL quartile. Multivariate liner regression analysis indicated that low serum 25(OH)D level (20 ng/mL may be required to maintain patients’ QOL in osteoporosis.

The vitamin-K-dependent gamma-glutamyl carboxylase (GGCX) carboxylates vitamin-K-dependent proteins including bone Gla protein (osteocalcin) and matrix Gla protein, which play important roles in bone metabolism. Therefore, GGCX polymorphism might explain in part individual susceptibility to osteoporosis. In the present study, polymorphisms in the exons of this gene were screened in Japanese elderly women and a non-synonymous single nucleotide polymorphisms (SNP) were found; c.8762 GA; (Arg325Gln). When the kinetic parameters of GGCX325-Gln and GGCX325-Arg were compared in vitro, Vmax/Km was significantly higher for GGCX325-Gln (944.4+/-9.21 pmol/30 min/mg/mM FLEEL) than for GGCX325-Arg (671.9+10.79 pmol/30 min/mg/mM FLEEL) (p=0.018). Then, association study of this polymorphism with forearm bone mineral density (BMD) of Japanese postmenopausal women (n=500, age 73.6+/-5.74) was conducted. As a result, the body mass index (BMI)-adjusted Z score in the subpopulation older than 75 years (n=207) was higher in those with 325-Gln (0.650+/-0.883, mean+/-SD) than those with 325-Arg/Gln or 325-Arg (0.133+/-0.650) (p=0.0383). This is the first report to demonstrate the different activities of GGCX between the common genotypes and their association with BMD.

The effects of bezafibrate and pravastatin on remnant-like lipoprotein particles (RLPs) and lipoprotein subclasses were compared in type 2 diabetes. Bezafibrate (400 mg/day) and pravastatin (10 mg/day) were given to 27 Japanese diabetics in a randomized crossover design. RLP cholesterol (RLP-C) and RLP triglyceride (RLP-TG) were measured by an immunoseparation technique. LDL and HDL were separated each into three subclasses (large, medium, small) and their cholesterol (C) contents were measured by an HPLC method. RLP-C was reduced more effectively by pravastatin (bezafibrate -16.0% vs. pravastatin -40.6%, P0.05), whereas RLP-TG was reduced more effectively by bezafibrate (-55.2% vs. -35.0%, P0.05). Further, pravastatin decreased large and small LDL-C levels equally (large; -23.6%; medium; -17.2%, small; -21.0%), while bezafibrate produced a relatively larger reduction in small LDL-C (-12.1; -16.9; -21.5%). Whereas bezafibrate significantly decreased large HDL-C and increased medium and small HDL-C (-49.6; 34.1; 35.8%), pravastatin significantly increased only medium HDL-C (5.2; 9.4; 5.9%). Bezafibrate reduced RLP-C and RLP-TG more effectively in patients with high TG levels, whereas pravastatin's effect was not markedly influenced by the initial TG level. Thus measurements of RLP-C, RLP-TG, and HPLC subclasses revealed that bezafibrate and pravastatin differently influence the lipoprotein status in type 2 diabetes.

Using cross-sectional and prospective analyses, the risk factors for macroangiopathy (MA) in nonobese Type 2 diabetic patients were evaluated. In the cross-sectional study, we determined a cutoff point for each variable at which changes in the prevalence of total MA reached statistically significant levels. In the prospective study, those who met more than four out of seven control criteria as set forth in the Multiclinical Study for Diabetic Macroangiopathy (MSDM) had less risk of MA in Type 2 diabetes initially diagnosed without MA compared with those who fulfilled less than three factors. These results suggest that multiple risk factor control is the most effective and reasonable way to lower the incidence of MA in Type 2 diabetes.

Increasing evidence indicates a significant role for vitamin K in bone metabolism and osteoporosis. In this study, we found a large geographic difference in serum vitamin K2 (menaquinone-7; MK-7) levels in postmenopausal women. Serum MK-7 concentrations were 5.26 +/- 6.13 ng/mL (mean +/- SD) in Japanese women in Tokyo, 1.22 +/- 1.85 in Japanese women in Hiroshima, and 0.37 +/- 0.20 in British women. We investigated the effect of Japanese fermented soybean food, natto, on serum vitamin K levels. Natto contains a large amount of MK-7 and is eaten frequently in eastern (Tokyo) but seldom in western (Hiroshima) Japan. Serum concentrations of MK-7 were significantly higher in frequent natto eaters, and natto intake resulted in a marked, sustained increase in serum MK-7 concentration. We analyzed the relation between the regional difference in natto intake and fracture incidence. A statistically significant inverse correlation was found between incidence of hip fractures in women and natto consumption in each prefecture throughout Japan. These findings indicate that the large geographic difference in MK-7 levels may be ascribed, at least in part, to natto intake and suggest the possibility that higher MK-7 level resulting from natto consumption may contribute to the relatively lower fracture risk in Japanese women.

We investigated the expression of parathyroid hormone-related protein (PTHrP) in atherosclerotic lesions and the role of PTHrP in the development of arterial neointima formation. Immunohistochemical staining of PTHrP in the neointima of rat aorta produced by balloon injury and of rat femoral artery produced by non-obstructive polyethylene cuff placement, and in the atherosclerotic lesion of human coronary artery was performed using anti-human PTHrP-(1-34) antibody. Anti-muscle actin antibody, HHF-35, and anti-macrophage antibody, HAM-56, were used to identify smooth muscle cells and macrophages, respectively. Immunoreactivity of PTHrP was detected in the thickened intima of rat and human lesions where the predominant cell types were smooth muscle cells or macrophages dependently on the lesion type. In the next series of experiments, we examined the effect of PTHrP on the development of cuff-induced intimal thickening of rat femoral artery. Either PTHrP-(1-34) or PTHrP-(7-34), a PTH/PTHrP receptor antagonist, suspended in pluronic F-127 gel was locally applied around the rat femoral artery. Intimal thickening induced by cuff placement was evaluated 2 weeks later. PTHrP-(1-34) dose-dependently inhibited intimal thickening determined as intima/media ratio and % stenosis whereas PTHrP-(7-34) dose-dependently enhanced that. These results suggest that PTHrP, which is expressed in atherosclerotic lesions, inhibits the development of neointimal formation.

Chromosomal mapping of the human estrogen receptor beta (ERbeta) gene by fluorescence in situ hybridization (FISH) reveals that ERbeta is located at human chromosome 14, region q23-24.1, where the aberration of DNA copy number in the bone disorders is frequently involved. Then, we investigated the association between dinucleotide (cytosine-adenine; CA) repeat polymorphism located in the flanking region of ERbeta gene and bone mineral density (BMD) in 204 healthy postmenopausal Japanese women. The genotype was classified into "A" through "O" according to the number of the repeats, from 18 to 32. BMD was expressed in Z score (a deviation from the weight-adjusted average BMD of each age using the standard deviation as a unit). When we separate the subjects into two groups bearing at least one I allele (26 CA repeats) and those who did not, the former subjects had significantly higher Z score of L2-4 BMD (mean +/- standard deviation; 0.674 +/- 1.53 vs 0.128 +/- 1.38; P = 0.027). These data suggest that genetic variation at the ERbeta locus may be associated with some determinants for BMD and the possible involvements of this polymorphism in the cause of postmenopausal osteoporosis in Japanese women.

Tibolone (Org OD14), (7alpha, 17alpha)-17-hydroxy-7-methyl-19-norpregn-5(10)-en-20-yn++ +-3-one, is a synthetic steroid with weak estrogenic, progestational, and androgenic properties. We investigated the prophylactic effects of tibolone on bone loss, bone strength, and plasma and urinary parameters in 8-month-old ovariectomized rats on a low-Ca diet. Oral administration of tibolone (0.03-3 mg/kg/day) was started immediately after ovariectomy (ovx) and continued for 3 months. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry. Oral administration of tibolone (1 or 3 mg/kg/day) significantly prevented a decrease in BMD and bone ash density (bone ash weight/volume) of the global femur, and BMDs in the femoral distal and proximal regions. Also in the lumbar vertebrae, the ovx-induced reduction in BMD was prevented by tibolone (1 and 3 mg/kg/ day) treatment, resulting in a significantly higher lumbar vertebral (L-2) bone compression strength compared to the ovx control group. Neither ovx alone nor supplemented with tibolone affected the BMD or bending strength of the femoral mid-diaphysial region. Tibolone (0.03-3 mg/kg/day) significantly reduced the ovx-induced increases in serum osteocalcin level. Furthermore, tibolone inhibited an increase in the urinary hydroxyproline/creatinine, pyridinoline/creatinine, and deoxypyridinoline/creatinine ratios induced by ovx. Tibolone also reduced body weight gain and serum cholesterol level, as has been reported for estrogen. These findings indicate that tibolone prevents reduction in bone mass associated with osteopenia by reducing increased trabecular bone resorption induced by a combination of ovx and a low-Ca diet.

The present study was performed to elucidate the mechanism underlying the anti-atherogenic action of estrogen. We investigated the effect of estrogen on intimal thickening of the rat femoral artery induced by cuff placement and further examined the effect of estrogen on migration and proliferation of vascular smooth muscle cells (VSMCs) in culture. Intimal thickening was significantly greater in males than in control females. Intimal thickening in females was increased to the level in males by ovariectomy. Estrogen replacement to ovariectomized rats reversed this effect. Proliferating cell nuclear antigen immunohistochemistry showed that in vivo proliferation of VSMCs contributed to the difference in intimal thickening. There was no difference in blood pressure and serum lipids, suggesting that estrogen directly acted on artery and inhibited intimal thickening. 17 beta-Estradiol (E2, 1-100 nmol/l) inhibited migration of cultured rat VSMCs, assayed using a microchemotaxis chamber, in a concentration-dependent manner. E2 (0.01-100 nmol/l), but not progesterone or testosterone, also inhibited [3H]thymidine incorporation in rat VSMCs in a concentration-dependent manner. Indomethacin, NG-monomethyl-L-arginine and methylene blue did not influence the inhibitory action of E2 on [3H]thymidine incorporation, suggesting that prostanoids and nitric oxide are not involved in the action of E2. E2 did not provoke VSMC injury, as measured by the release of incorporated [3H]2-deoxy-D-glucose. These results suggest that the inhibition of migration and proliferation of VSMCs contributes to the inhibitory effect of estrogen on intimal thickening.

It has been shown that vasopressin receptors are upregulated in the brain and that the central vasopressin pathway is involved in the development of deoxycorticosterone acetate (DOCA)-salt hypertension. However, it is unclear whether central vasopressin, in itself, is essential for this type of hypertension. To clarify this issue, the effect of centrally administered vasopressin on the development of DOCA-salt hypertension was studied in homozygous Brattleboro rats which genetically lack vasopressin. In homozygous Brattleboro rats, treatment with intracerebroventricular infusion of vasopressin (1 ng/h) alone or DOCA-salt (weekly subcutaneous injection of 30 mg/kg deoxycorticosterone acetate and 0.3% NaCl to drink) alone had no effect on systolic blood pressure (SBP). On the other hand, hypertension was partially restored in homozygous Brattleboro rats treated with intracerebroventricular infusion of vasopressin and DOCA-salt (SBP: 175 +/- 4 mmHg), although the magnitude of elevation of SBP was one-third of that in Long Evans rats treated with DOCA-salt (278 +/- 15 mmHg). These hypertensive homozygous Brattleboro rats showed an increase in fluid intake and urinary sodium excretion, as observed in DOCA-salt hypertensive Long Evans rats. These results suggest that central vasopressin is required for the complete development of DOCA-salt hypertension and the mechanism is, in part, due to enhanced sodium intake through the additive effect of central vasopressin and DOCA-salt.

Clinical and experimental studies showed that estrogen has antiatherogenic effects. We previously demonstrated that the estrogen receptor (ER) mRNA and protein are expressed in vascular smooth muscle cells (VSMC) derived from rat aorta. Here, the expression of isoforms of the ER was examined in VSMC. Reverse transcriptase-polymerase chain reaction using specific primers for rat ER cDNA was performed from RNA of rat VSMC. This revealed the existence of ER cDNA that is shorter than the wild-type ER cDNA. Sequencing of the amplified products identified three isoforms of the ER and the wild-type ER. These ER mRNA isoforms lacked the region corresponding to exon 4, exon 4 and 5, and exon 3 and 4. Therefore, they were designated as ERdelta4 isoform, ERdelta4/5 isoform and ERdelta3/4 isoform, respectively. Chloramphenicol acetyltransferase assay was performed with these ER isoforms constructed into the expression vector and the reporter plasmid containing the estrogen responsive element. The assay showed that these ER isoforms lost estrogen-dependent transactivation activities and that ERdelta4/5 isoform has a inhibitory effect on normal estrogen action when it was cotransfected with the wild-type ER. These ER isoforms might be involved in the regulation of VSMC by estrogen.

Human α -1-protease inhibitor ( α -1-Pi) has been known to be a highly polymorphic protein. We hypothesized that antiprotease activity of each phenotype M of α l-protease inhibitor (PiM) might be different among smokers and that a variation of decrease in pulmonary function for a given amount of cigarette smoking might be associated with PiM phenotypes. To test this, we investigated the effect of cigarette smoking on pulmonary function in each PiM phenotype. The serum level of α l-Pi was measured by the turbidimetric immunoassay and the distribution of PiM phenotypes was determined using isoelectric focusing technique in 247 healthy subjects and 20 COPD patients. Serum levels of α -1-antitrypsin of healthy and COPD subjects were 205.1±31.1 and 179.2±44.4 (±SD) mg/dL, respectively (p>0.01). The frequency of each PiM phenotype in healthy subjects was shown as follows: M 1 , 0.555; M 1 M 2 , 0.328; M 2 , 0.041; M 1 M 3 , 0.057; M 2 M 3 , 0.016; M 3 , 0.004. The difference in the distribution of PiM phenotypes between healthy and COPD subjects was not significant. Single- and multiple-regression analyses showed that the ratio of FEV 1 to forced vital capacity (FVC), in which FEV 1 is expressed as percentage of FVC, the maximum flow rate at 50% of FVC divided by measured body height ( V ˙ 50 /Ht), and the maximum flow rate at 25% of FVC divided by body height ( V ˙ 25 /Ht) were closely related to age and that V ˙ 25 /Ht also was related to smoking index. However, PiM phenotype was unrelated to those pulmonary function variables. We conclude that PiM phenotype is not a major determinant of difference in magnitude of pulmonary impairments caused by cigarette smoking in each individual.

It is well known that peripheral vasopressin (VP) is essential for the development and maintenance of DOC-salt hypertension. It is, however, still unclear whether central VP is involved in this type of hypertension. Therefore, the aim of this study was to clarify the role of central VP in the regulation of blood pressure in DOC-salt hypertension. In order to examine this issue, three series of investigations were performed. First, a novel vasopressin V1 antagonist (OPC21268) was administered intravenously to DOC-salt hypertensive rats, and mean arterial blood pressure (MABP) and heart rate (HR) were recorded. Second, the concentration of VP in the perfusate of microdialysis of cerebrospinal fluid (CSF) was determined in DOC-salt hypertensive and control rats. Finally, intracerebroventricular (i.c.v.) administration of a V1 antagonist was performed in DOC-salt hypertensive rats to determine the central mechanism of hypertension. Intravenous administration of a V1 antagonist had no effect on MABP and HR. There was no difference in VP in the perfusate of CSF between DOC-salt hypertensive and control rats. I.c.v. administration of a V1 antagonist significantly decreased MABP and HR in a dose-dependent manner in DOC-salt hypertensive rats (P < 0.05-0.01). These results suggest that central VP is involved in the maintenance of DOC-salt hypertension, and the mechanism is, in part, mediated by upregulation of the V1 receptor.

We previously reported that follistatin, an activin-binding protein, is produced in arteriosclerotic lesions. Here, the expression of activin-A which promotes the growth of vascular smooth muscle cells was examined in arteriosclerotic lesions of WHHL (Watanabe heritable hyperlipidemic) rabbits. Activin-A mRNA was detected in normal aorta by reverse transcriptase-polymerase chain reaction using specific primers for activin-A cDNA and was increased remarkably in arteriosclerotic lesions. In addition, using the cloned rabbit activin-A cDNA, RNA probe was prepared and in situ hybridization histochemistry was performed. Activin-A transcripts were detected abundantly in neointima of the diseased artery. Furthermore, immunohistochemistry also detected activin-A at the protein level. These observations suggest that activin-A is a cytokine expressed in arteriosclerotic lesions and might be involved in the pathogenesis of atherosclerosis.

ER mRNA was detected as 6.0 kb band by Northern blot analysis in vascular smooth muscle cells (VSMC) derived from rat aorta. The presence of ER mRNA in VSMC was confirmed by reverse transcriptase-polymerase chain reaction using specific primers for rat ER cDNA. In addition, the immunocytochemistry of ER was performed in VSMC using a monoclonal anti-ER antibody which recognizes DNA-binding domain of ER. The immunoreactivity was distributed in the cytoplasm as well as in the nuclei. Thus, the expression of ER in VSMC was demonstrated at both the protein and the mRNA level. Furthermore, the expression of c-fos mRNA in VSMC was found up-regulated by 17 beta-estradiol treatment within 30 min. The observation that VSMC possess ER and respond to estrogen supports the idea that estrogen may directly influence vascular cell system through the ER.

A human osteosarcoma cell line, HOS TE85 cells, and a mouse osteoblastic cell line, MC3T3-E1 cells, were cultured for 3 days in a medium containing various concentrations of menaquinone-4 (vitamin K2). As a result, the proliferation of HOS cells was suppressed by vitamin K2 in a dose dependent manner up to 56% of control by 10(-7)M of vitamin K2 and that of MC3T3-E1 cells was suppressed to 84% of control by 10(-6)M of vitamin K2. Vitamin K2 increased alkaline phosphatase activity in both kinds of cells. Warfarin counteracted the effect of vitamin K2 on osteoblastic cell proliferation. Our results show that vitamin K2 modulates proliferation and function of osteoblastic cells by some mechanisms including gamma-carboxylation system.

To study the effect of a large dose of 24R,25(OH)2D3 on bone metabolism, we treated vitamin D-replete rabbits with the agent for eight weeks. Fifteen rabbits 20 weeks of age were divided into three groups of five animals each. Group I received only the vehicle; groups II and III were given the agent at doses of 10 μg/kg/d, and 100 μg/kg/d, respectively. Through the dosing period, serum calcium, phosphorus, alkaline phosphatase, and creatinine levels were not altered. By the end of the experiment, serum 1,25(OH)2D or serum 25(OH)D levels did not change, nor did the PTH level. Serum 24,25(OH)2D levels for groups I, II, and III were 5.25 ±3.40, 76.16 ± 19.90 (p < .01), and 199.0 ± 30.90 (p < .01) ng/ml, respectively. The bone mineral content (BMC) significantly increased in group III. The percentages of BMC increase in group III over group I were 14.5% on the femur, 34.1% (p < .01) on the sixth lumbar vertebra, and 23.3% (p < .05) on the seventh lumbar vertebra. A marked increase of bone mineral densities in the cancellous bone-rich regions was seen in group III. Bone histomorphometry on the seventh lumbar vertebra demonstrated that both the eroded surface and the osteoclast number were reduced and the surfaces indicating bone formation such as the osteoid surface and the tetracycline double labeled surface were also reduced. However, both the osteoid thickness and the mineral apposition rate increased and the mineral formation rate at the tissue level remained approximately equal to that in the control. These results clearly indicate that 24R,25(OH)2D3 reduces bone turnover and stimulates osteoblastic functions and warrant further studies on its effects on differentiation of osteoclasts and the function of osteoblasts.

The senescence accelerated mouse (SAM) has recently been characterized as a unique model to investigate age-related disorders, including amyloidosis, cataract, osteoporosis and dementia. However, little is known as to the properties of the lung in these animals. Tobacco smoke is also associated with enhanced loss of elastic recoil and the development of emphysema. We have attempted to examine morphological as well as biochemical changes of the distal lung in SAM-P/2, as the senescence-prone series and SAM-R/1, as the senescence-resistant series. The animals were intermittently exposed to tobacco smoke or air by Hamburg II machines for 5 weeks. Then both groups of animals were killed for histologic and biochemical study. Compared with SAM-R/1, SAM-P/2, even with air exposure, showed a higher value of the mean linear intercept without alveolar wall destruction. It became even greater due to tobacco exposure with emphysematous change. Tobacco exposure accumulated inflammatory cells into alveoli in SAM-P/2, but not in SAM-R/1. Oxygen radical generation by those cells was also higher in SAM-P/2. Analysis of bronchoalveolar lavage fluid in SAM-P/2 after tobacco exposure disclosed increases in albumin content, total protein content and elastase-like activity. There were decreases in the ratio of elastase inhibitory capacity (EIC) to trypsin inhibitory capacity (TIC), contents of glutathione and total free thiol groups. Moreover, SAM-P/2 showed significantly lower EIC/TIC ratio in serum, even with air exposure, than that of SAM-R/1. These results indicate that SAM-P/2 can be a good model for the study of natural evolution of the aging lung as well as its susceptibility to tobacco smoke in the development of emphysema.

This study was undertaken to examine the possibility that parathyroid hormone promotes the production of interleukin 1 and 6 in MC3T3-E1 osteoblastic cells derived from mouse calvaria. The cells were incubated in serum-free medium with or without synthetic human parathyroid hormone(1-34). The concentrations of interleukin 1 and 6 in the culture medium were determined by using specific bioassay. The cells cultured without parathyroid hormone for 24 hr released both of interleukins, and parathyroid hormone stimulated the release in a dose-dependent manner. When the cells were cultured with 10(-6) M parathyroid hormone, the release of both interleukins from the cells remained higher than control up to 144 hr. These results suggest that interleukin 1 and 6 release stimulated by parathyroid hormone may be involved in the bone resorbing activity of the hormone.

Biological activity of 24- epi -1α,25-dihydroxyvitamin D-2 (24- epi -1,25(OH) 2 D 2 ) and 1α,25-dihydroxyvitamin D-7 (1,25(OH) 2 D 7 ), the 22,23-dihydro derivative of the former compound, was investigated. Both of the vitamin D derivatives stimulated intestinal calcium transport and calcium mobilization from bones in rats; however, the effect was about 50% of that of 1α,25-dihydroxyvitamin D-3 (1,25(OH) 2 D 3 ). On the other hand, 24- epi -1,25(OH) 2 D 2 and 1,25(OH) 2 D 7 inducement of HL-60 human leukemia cell differentiation was comparable to that of 1,25(OH) 2 D 3 . Accordingly, the differentiation-inducing activity of 24- epi -1,25(OH) 2 D 2 and 1,25(OH) 2 D 7 was much greater than their ability to stimulate calcium metabolism. In contrast to 1,25(OH) 2 D 3 , 24- epi -1,25(OH) 2 D 2 and 1,25(OH) 2 D 7 exerted little hypercalcemic activity in mice. These results suggest that both vitamin D derivatives will be useful as anti-tumor agents.

An in vitro study of how platelet aggregation would be inhibited by the combination of aspirin or ticlopidine irreversibly inhibitory to platelet aggregation and trapidil or dipyridamole reversibly inhibitory, was carried out. The measured 50% inhibition concentrations indicated that aspirin was most inhibitory to collagen-induced platelet aggregation, followed by trapidil, ticlopidine and dipyridamole in decreasing sequence of inhibition. The combination of either aspirin or ticlopidine with trapidil inhibited platelet aggregation more intensely than the combination of either agent with dipyridamole. Thus, in clinical use of aspirin or ticlopidine, it may be expected that the lower dosage of aspirin or ticlopidine with lower frequencies of side effects inhibits platelet aggregation effectively with the combination of trapidil rather than dipyridamole.

The effects of high frequency oscillatory ventilation (HFOV) and conventional mechanical ventilation (CMV) on tracheal secretion were compared in 6 anesthetized dogs. Using a double-balloon endotracheal catheter, 5 ml of saline was instilled into an isolated tracheal segment during HFOV and CMV for 10 min respectively. Two eicosanoids, 15-hydroxyeicosatetraenoic acid (15-HETE) and 11-dehydrothromboxane B2 (11-dehydro-TXB2) were measured by radioimmunoassay in each sample. HFOV (stroke volume: 6 ml/kg, f: 10 Hz, bias flow: 5 l/min) and CMV (stroke volume: 12 ml/kg, f: 15/min) were performed in random sequence and achieved comparable gas exchange. The concentration of 15-HETE in tracheal fluid during HFOV (87 +/- 67 pg/ml) was decreased to less than half of that during CMV (286 +/- 184 pg/ml, P less than 0.05), while there was no significant change of 11-dehydro-TXB2 either in tracheal fluid or in plasma. This reduction of 15-HETE was tended to be enhanced by vagotomy (HFOV: 42 +/- 14, CMV: 120 +/- 103 pg/ml) with the concentration ratio of CMV/HFOV remaining unchanged. HFOV may provide hitherto unrecognized advantage over CMV by reducing airway secretion of 15-HETE, a potent inflammatory mediator.

We investigated the effects of intravenous bolus of endothelin-1 on the metabolism of eicosanoids and oxygen radicals in the distal lung unit of the rat. Intravenous bolus of endothelin-1 caused a significant increase in 15-hydroxyeicosatetraenoic acid of bronchoalveolar lavage fluid and oxygen radicals produced by the bronchoalveolar cells. Endothelin-1 exhibited a stimulatory effect on the 15-lipoxygenase activity in the lung homogenate. Thus, endothelin-1 may contribute to the inflammatory and hyperreactive process of lungs, by enhancing the release of 15-hydroxyeicosatetraenoic acid and oxygen radicals in the distal lung unit.

The effects of estradiol on the endogenous fatty acid (specifically, arachidonic acid) composition of cellular phospholipid fractions and the 12-lipoxygenase activity in rat platelets in vivo were studied. Estradiol had no significant effect on the endogenous fatty acid composition of cellular phospholipid fractions. However, estradiol significantly increased 12-lipoxygenase activity in platelets in a dose-dependent manner. The stimulatory effect of estradiol on platelet lipoxygenase was blocked by the anti-estrogen nafoxidine hydrochloride which was injected simultaneously together with estradiol in vivo, suggesting that the effect in target cells was due directly to estradiol.

The migration of rat aortic smooth muscle cells was measured in modified Boyden chambers. Smooth muscle cells were motile in vitro and their migration was stimulated (time- and dose-dependently) by a platelet-derived factor. Treatment of platelets with indomethacin resulted in a significant increase in smooth muscle cell migration, whereas treatment with 5,8,10,14-eicosatetraenoic acid inhibited it. Purified 12-L-hydroxy-5,8,10,14-eicosatetraenoic acid at a very low concentration (6 x 10(-15)-6 x 10(-13) g/ml) significantly stimulated smooth muscle cell migration. The locomotion induced by 12-L-hydroxy-5,8,10,14-eicosatetraenoic acid was chemokinetic. These findings point to the physiological importance of a platelet 12-lipoxygenase product of arachidonic acid in the early phase of atherosclerosis.

To determine whether aortic smooth muscle cells possess estradiol receptors or not, an estradiol binding study has been performed in cultured rat aortic smooth muscle cells by using an intact-cell assay. Specific binding for estradiol is shown by the cells, and the binding reaches a plateau after 15 min of incubation at 37°C. The binding curve shows a saturable binding process. Scatchard analysis reveals a single population for estradiol binding with a dissociation constant of 5.0 X 10 −8 M and specific binding sites of 64 fmole per 10 6 cells (38,500 sites per cell). Molecular specificity shows highly specific binding with estradiol. Among various steroids tested, only testosterone at 10 −5 M competes slightly (9.3%) with the estradiol-specific binding. These data indicate the existence of specific, high-affinity and limited-capacity binding sites for estradiol in rat aortic smooth muscle cells. This accords with the concept that estrogen responsiveness in aortic smooth muscle cells is mediated through the estrogen-receptor binding in the cells.

Since elevated thromboxane A2 synthesis could be expected to lead to microvascular injury in diabetic patients, it is important to determine the relationship between thromboxane A2 synthesis and diabetic microvascular complications. In the present study, the activity of thromboxane A2 synthesis in platelets was assessed in 57 Type 2 (non-insulin-dependent) diabetic patients by measuring the conversion of exogenously added 14C-arachidonic acid into 14C-thromboxane B2. The activity of thromboxane synthesis was significantly higher in diabetic patients than in 16 age-matched control subjects (2.61 +/- 0.07 vs 1.95 +/- 0.12 microgram . 10(9) platelets-1 . 3 min-1, respectively, p less than 0.001). When the diabetic patients were divided into three groups (nil, background, and proliferative retinopathy) on the basis of severity of diabetic retinopathy, there was a trend to increased thromboxane synthesizing activity as diabetic retinopathy develops. However, no statistically significant changes were demonstrated among these three groups. In the diabetic patients, a positive correlation was found between thromboxane synthesizing activities and glycosylated hemoglobin values (biochemical indicator of long-term glycemic control), but not between the activities and plasma glucose levels. To ascertain the effect of desirable diabetic treatment on thromboxane synthesizing activity in platelets, 9 newly diagnosed patients and 6 poorly controlled patients were examined. During treatment, all patients had declining plasma glucose and glycosylated hemoglobin levels. Thromboxane synthesizing activities in 6 patients treated by insulin decreased significantly during treatment (3.16 +/- 0.17 to 2.49 +/- 0.22 microgram . 10(9) platelets-1 .3 min-1, p less than 0.01), but 9 diabetic patients treated by diet or sulphonylureas still maintained their elevated thromboxane synthesizing activity levels (2.76 +/- 0.24 to 2.66 +/- 0.25 microgram . 10(9) platelets-1 .3 min-1,NS). These results suggest that the increased thromboxane synthesizing enzyme system is involved in the abnormal platelet function in diabetes independently of diabetic retinopathy, and that appropriate metabolic control using insulin might be successful in lowering the increased thromboxane synthesizing activity.

The relationship between arterial calcification and serum estradiol levels was studied in 72 postmenopausal female and 59 male subjects. In both sexes, subjects with iliac artery calcification had rather lower serum estradiol levels (8.4 +/- 1.4 pg/ml in the females, and 19.2 +/- 2.5 pg/ml in the males) than controls (16.1 +/- 1.6 pg/ml in the females, and 29.7 +/- 2.4 pg/ml in the males). The bone mineral content of females with iliac artery calcification (0.44 +/- 0.02 g/cm2) was lower than controls (0.52 +/- 0.01 g/cm2); a positive correlation between serum estradiol levels and bone mineral content was found in the females. However, bone mineral content did not significantly differ between males with and without arterial calcification (0.67 +/- 0.03 g/cm2 in the former, and 0.65 +/- 0.02 g/cm2 in the latter). These results indicate that arterial calcification and increased bone resorption are both individual results of estrogen deficiency.

The effect of triiodothyronine (T 3 ) on prostacyclin production in rat aortic smooth muscle cells was investigated by using an intact cell assay system. T 3 at its physiological concentrations has no significant effect on smooth muscle cell proliferation, but it does significantly stimulate prostacyclin production by the cells. Maximum stimulation of prostacyclin production is obtained when cells are treated with T 3 for 4 consecutive days. The dose—response curve shows a linear relationship between the stimulation of prostacyclin production and T 3 concentrations in the range 0.007–10 μg/dl. The maximal prostacyclin production by T 3 -treated cells (at a concentration of 10 μg/dl), is 270% compared with control cells. T 3 treatment shows no significant effect on phospholipase (and/or lipase) activities. Our results suggest that thyroid hormone might play an important physiological role in the protection of arteries from atherosclerotic changes by stimulating prostacyclin production in arterial smooth muscle cells.

Twelve volunteers (mean age, 60.7 ± 4.2 years) were treated with placebo for the first week and then given partially purified eicosapentaenoic acid (EPA, 67% purity) at 2 g per day for 4 weeks. Significant decreases in ADP-, collagen- and adrenalin-induced platelet aggregation were observed at 2 and 4 weeks after EPA treatment, together with an increase in the plasma ratio of EPA to arachidonic acid and in platelet phospholipids. It was concluded that the administration of partially purified EPA was effective in decreasing platelet aggregation, possibly by changing the platelet ratio of EPA to arachidonic acid.

Female silver eels ( Anguilla japonica ) were matured with repeated injections of chum salmon pituitary homogenate. Blood samples and ovaries were taken at various stages of ovarian development for the analysis of serum immunoreactive calcitonin (CT), Ca content, and gonadosomatic index. Serum CT levels gradually increased in accordance with an increase in gonadosomatic index and the highest level was observed at the time of ovulation. An increase in serum Ca level was also observed during ovarian development. These results suggest an involvement of CT in sexual maturation in the eel.

Serum sodium, potassium, chloride, calcium, magnesium, and osmotic pressure were measured at 0, 1, 3 and 5 hr after the ip injection of pure eel calcitonin (5 MRC U/head) into the normal calcemic Japanese eel ( Anguilla japonica ) kept in fresh water. Calcitonin did not cause any significant changes in these serum parameters in the eels. Furthermore, eel calcitonin did not lower the serum calcium in the hypercalcemic eels.

Prostaglandin biosynthetic activity in cultured rat aortic smooth muscle cells was investigated as a function of age by both intact cell and cell-free homogenate assays. The total cyclooxygenase activity for prostaglandin biosynthesis is the same in cells from young and old rats. However, cells from young rats proceduce more prostacyclin than prostaglandin E2, and cells from old rats produce more prostaglandin E2 than prostacyclin. Age-related decrease in prostacyclin biosynthesis is also found when protaglandin H2 is used as substrate. Lower prostacyclin and higher prostaglandin E2 biosynthetic activity in aortic smooth muscle cells from aged rats may contribute to the direct explanation of pathogenesis of spontaneous atherosclerosis and artial thrombosis in aged humans and other mammals.

A patient with diffuse gastrointestinal polyposis, abnormal skin pigmentation, loss of hair and nails, and hypoproteinemia is described. Data on nine other patients with this syndrome described in the literature are reviewed and possible mechanisms responsible for hypoproteinemia and the changes of ectodermal structures are discussed. This syndrome differs from the Peutz-Jeghers syndrome and from familial polyposis of the colon and should be called the "Cronkhite-Canada syndrome," derived from the names of those who first described it.

A method for the separation and estimation of DNP derivatives of 13 amino acids by a gas chromatographic technique is described. The separation was carried out with 1.0% XE-61 or 1.5% SE-30 as the stationary phase, and with a hydrogen flame ionization detector and temperature programmer. A method for the determination of the free amino acids in serum by gas chromatography was also investigated.