Smoking and lipid-related indices in patients with diabetes mellitus

AIMS

Lipid-related indices, including the ratio of LDL cholesterol to HDL cholesterol, the ratio of triglycerides to HDL cholesterol and lipid accumulation product, are known to be good discriminators for cardiovascular disease. The aim of this study was to clarify the relationships between smoking and the lipid indices in patients with diabetes.

METHODS

Subjects were those who had been diagnosed as having diabetes mellitus at annual health check-ups at their places of work (n = 2563). The subjects were divided into three groups of non-smokers, light smokers (≤ 20 cigarettes/day) and heavy smokers (> 20 cigarettes/day). The relationships between smoking and the lipid indices were investigated.

RESULTS

Both in all subjects and in the subjects without a habit of alcohol drinking, the LDL cholesterol:HDL cholesterol ratio and the log-transformed triglyerides:HDL cholesterol ratio tended to be higher with an increase in the amount of smoking, and the log-transformed lipid accumulation product was significantly higher in heavy smokers than in non-smokers. In the non-alcohol drinking subjects, the odds ratios of heavy smokers vs. non-smokers for high LDL cholesterol:HDL cholesterol ratio [2.32 (95% CI 1.40-3.84)], for high triglycerides:HDL cholesterol ratio [1.69 (95% CI 1.06-2.69)] and for high lipid accumulation product [1.65 (95% CI 1.02-2.67)] were significantly higher than a reference level of 1.00. The associations between smoking and the lipid indices were weaker in alcohol drinkers than in non-drinkers.

CONCLUSIONS

In patients with diabetes, the levels of lipid-related indices were higher in smokers than in non-smokers, and cardiometabolic disorders, reflected by high lipid indices, are thought to be involved in the proneness of smokers to develop atherosclerotic cardiovascular disease.

Inhibition of CXCL10 release by monomeric C3bi and C4b

Cellulose acetate (CA) beads are often used for leucocyte apheresis therapy against inflammatory bowel disease. In order to clarify the mechanism of the anti-inflammatory effects of CA, global analysis of the molecules generated in blood by the interaction with CA beads was performed in this study. An activated medium was collected from whole blood that had been preincubated with CA beads, and the effects of the CA-activated medium on leucocyte function were investigated. Fresh blood was stimulated with lipopolysaccharide (LPS) or interferon (IFN)-β in the presence of the activated medium, and levels of chemokines and cytokines, including CXCL10 (IFN-inducible protein-10), and phosphorylated STAT1 (signal transducer and activator of transcription 1), which is known to be essential for CXCL10 production in leucocytes, were measured. IFN-β- or LPS-induced CXCL10 production, expression of CXCL10 mRNA and phosphorylation of STAT1 were significantly reduced in the presence of the medium pretreated with CA beads compared with the control without the CA bead treatment. The factors inhibiting CXCL10 production were identified as the C3 and C4 fragments by mass spectrometry. The monomeric C3bi and C4b proteins were abundant in the medium pretreated with CA beads. Furthermore, purified C3bi and C4b were found to inhibit IFN-β-induced CXCL10 production and STAT1 phosphorylation. Thus, STAT1-mediated CXCL10 production induced by stimulation with LPS or IFN was potently inhibited by monomeric C3bi and C4b generated by the interaction of blood with CA beads. These mechanisms mediated by monomeric C3bi and C4b may be involved in the anti-inflammatory effects of CA.

Alcohol intake and atherosclerotic risk factors in normotensive and prehypertensive men

BACKGROUND

The purpose of this study was to determine whether relationships between alcohol intake and atherosclerotic risk factors were different in normotensive and prehypertensive persons.

METHODS

Japanese men aged 35-60 years who showed normal blood pressure (n = 4,778) or prehypertension (n = 9,728) without any drug therapy for hypertension were divided into non, light (<22 g ethanol/day), heavy (≥ 22 and < 44 g ethanol/day) and very heavy (≥ 44 g ethanol/day) drinkers.

RESULTS

In subjects with prehypertension, body mass index (BMI) and waist circumference were significantly lower and smaller, respectively, in light, heavy and very heavy drinkers than in nondrinkers. In subjects with normal blood pressure, BMI was significantly lower in light and heavy drinkers but not in very heavy drinkers than in nondrinkers, and waist circumference was not significantly different in non, light and heavy drinkers and was significantly larger in very heavy drinkers than in nondrinkers. Both in the prehypertensive and normotensive groups, compared with nondrinkers, hemoglobin A(1C) and low-density lipoprotein (LDL) cholesterol were significantly lower and high-density lipoprotein (HDL) cholesterol was significantly higher in light, heavy and very heavy drinkers, and log-converted triglycerides was significantly higher in very heavy drinkers.

CONCLUSIONS

The association of alcohol intake with a lower occurrence of obesity is stronger in prehypertensives than in normotensives, while the associations of alcohol intake with lower occurrences of hyperglycemia and abnormal cholesterol profile, such as lowered HDL cholesterol and elevated LDL cholesterol, and a higher occurrence of elevated triglycerides are similar in normotensive and prehypertensive persons.

Vasorelaxant Effect of Trapidil on Human Basilar Artery

We have investigated the vasorelaxant effect of trapidil on human isolated basilar artery. Trapidil (10−5-10−4  m) dose-dependently caused relaxation in vascular strips with or without endothelium, with no significant difference between the two types of strips. The relaxation responses were not inhibited by atropine, propranolol or methylene blue. Trapidil increased the concentration of 6-keto-PGF1α, a prostacyclin degradation product, released from an artery ring in the incubation medium, but trapidil-induced relaxation was not inhibited by indomethacin. Pretreatment of vascular strips with 10−5  m trapidil increased the relaxation responses to forskolin and dibutyryladenosine cyclic monophosphate but not to sodium nitroprusside or 8-bromoguanosine cyclic monophosphate. Trapidil induced a significant increase in the cAMP concentration but not in the cGMP concentration in artery strips. These results suggest that the relaxation response to trapidil is not caused by prostacyclin release or an increase in cGMP in the smooth muscle, but possibly by an increase in the cAMP levels, probably via an inhibitory effect on cAMP phosphodiesterase.

INFLUENCE OF DRINKING ALCOHOL ON ATHEROSCLEROTIC RISK IN ALCOHOL FLUSHERS AND NON-FLUSHERS OF ORIENTAL PATIENTS WITH TYPE 2 DIABETES MELLITUS

AIMS

Facial flushing caused by alcohol drinking is a typical symptom of high sensitivity to alcohol in orientals. We investigated whether drinking alcohol influences atherosclerotic risk factors in alcohol flushers and non-flushers in patients with diabetes mellitus.

METHODS

A cross-sectional study was performed using 225 subjects with type 2 diabetes. Sensitivity to alcohol was surveyed by a questionnaire on facial flushing. Subjects were divided into three groups by average amount of alcohol drinking (non-drinkers; light drinkers: <140 g/week; heavy drinkers: 140 g/week or more).

RESULTS

Systolic blood pressure and blood HDL cholesterol were significantly higher in heavy drinkers than in non-drinkers. There were no significant differences in body mass index, blood pressure, blood total cholesterol, HDL cholesterol, uric acid, fibrinogen and sialic acid levels in flushers and non-flushers. In alcohol flushers, diastolic blood pressure and HDL cholesterol in heavy drinkers were significantly higher than those in non-drinkers, and systolic blood pressure was significantly higher in heavy drinkers than in non-drinkers and light drinkers. On the other hand, blood pressure and HDL cholesterol in non-flushers were not significantly different among non-, light and heavy drinkers. Serum total cholesterol was not significantly different among the three drinking groups both in flushers and non-flushers.

CONCLUSIONS

Blood pressure and HDL cholesterol are more prone to be affected by drinking in flushers than in non-flushers, suggesting that alcohol sensitivity evaluated by flushing response due to drinking alcohol should be taken into account when the effects of alcohol drinking on atherosclerotic risk factors are considered in oriental patients with type 2 diabetes mellitus.

Isokinetic external rotation strength of shoulder : correlation with age and muscle size

The purpose of this study was to determine the correlation between quantitative (cross sectional areas) evaluation of the posterior cuff muscles and mechanical strength in asymptomatic shoulders with special reference to aging. The cross-sectional area of the combined infraspinatus and teres minor muscles were measured, in the sagittal oblique magnetic resonance images, in eighty-one patients with a mean age of 44.06 years (range 19 - 74). These areas were correlated with the measured isokinetic strength in external rotation at angular velocities of 60 deg/s and 180 deg/s using Cybex 770 NORM. The results show that there was a gradual decrease in size of the muscles as the age of the individual increases. A strong correlation was found between aging and combined cross-sectional area and peak torque as well. The correlation between combined cross-sectional area and peak torques at both angular velocities were less strong. Further, the correlation between the peak torque/cross-sectional area ratio with aging was also less significant, which may imply that the decrease in the muscle strength was greater than the change in muscle area. Our results suggest that there may be other qualitative and biochemical factors that may determine the true strength of the muscles in the aged population.

Age-dependent relation of serum sialic acid concentration to aortic pulse wave velocity in type 2 diabetes

OBJECTIVE

The purpose of this study was to determine whether age affects the significance of serum sialic acid concentration as a marker of atherosclerosis in patients with diabetes.

METHODS

In this cross-sectional study, we investigated the relationship of serum sialic acid concentration to aortic pulse wave velocity (a-PWV) and the effects of age on this relationship in patients with type 2 diabetes.

RESULTS

In the elderly (70 years or over) diabetic patients, a-PWV showed a significant positive correlation with serum sialic acid. This relationship was also significant after adjustment for age, duration of diabetes, body mass index, systolic blood pressure, LDL cholesterol, HDL cholesterol and fibrinogen levels. In elderly diabetic patients, a-PWV also showed a significant positive correlation with age and duration of diabetes and a significant negative correlation with serum HDL cholesterol level. On the other hand, in the younger (31-60 years) diabetic patients, there was no significant correlation between serum sialic acid level and a-PWV, while a-PWV showed significant positive correlations with age, duration of diabetes and plasma fibrinogen level.

CONCLUSIONS

Serum sialic acid level reflects atherosclerosis in elderly diabetic patients but not in younger diabetic patients. This may explain recent controversial findings regarding the relationship between serum sialic acid level and incidence of coronary heart disease in diabetes.

New simple method for purification of class I alcohol dehydrogenase

AIMS

The purpose of this study was to develop a new simple method for purification of rat class I alcohol dehydrogenase (ADH, EC 1.1.1.1).

METHODS AND RESULTS

Immobilized p-hydroxyacetophenone was used as a ligand for affinity chromatography for the initial purification step after ammonium sulfate precipitation of the cytosolic fraction of rat liver. Then the eluant was separated by using ion-exchange chromatography, and homogenous class I ADH, as judged by the results of SDS-PAGE and confirmed by the results of the amino-acid sequence of peptides degraded from a 39 kDa protein, was obtained with a high yield (57%). The purified ADH showed kinetic constants of 1.3 mmol/l for Km and 62.4 per min for Kcat with ethanol as a substrate. ADH was also successfully purified from yeast by a similar method using p-hydroxyacetophenone affinity chromatography.

CONCLUSIONS

This simple method involving only two chromatographic procedures may be very useful for purification of ADH.

Relation of serum sialic acid to blood coagulation activity in type 2 diabetes

The level of serum sialic acid, which is known to reflect atherosclerotic progress and to be related to the incidence of cardiovascular diseases, is increased in patients with diabetes. To elucidate the mechanism of the relation of serum sialic acid to fibrinogen, the relationship between serum sialic acid and markers of blood coagulation activity was investigated in type 2 diabetic patients. The concentration of serum sialic acid showed significant positive correlations with blood platelet count and with plasma concentrations of fibrinogen, D-dimer, thrombin-antithrombin III complex and plasmin-alpha2 plasmin inhibitor complex. These relationships were still significant after adjustment for age, sex, smoking history, body mass index, hemoglobin A, mean arterial pressure and low-density lipoprotein cholesterol. The correlation coefficient of blood fibrinogen with serum sialic acid was still significant after adjustment for D-dimer, thrombin-antithrombin III complex or plasmin-alpha2 plasmin inhibitor complex. On the contrary, blood fibrinogen showed no significant correlation with D-dimer, thrombin-antithrombin III complex or plasmin-alpha2 plasmin inhibitor complex, although an increase in blood fibrinogen is known to be an atherosclerotic risk factor. These results suggest that the serum sialic acid level reflects blood coagulation activity in type 2 diabetic patients and is related to blood fibrinogen level independently of blood coagulation activity.

Hypothalamic growth hormone secretagogue receptor regulates growth hormone secretion, feeding, and adiposity

Growth hormone secretagogues (GHSs) stimulate GH secretion and food intake. GHS receptor (GHS-R) mRNA has been identified mainly in the arcuate nucleus (Arc) and ventromedial nucleus of the hypothalamus and in the pituitary. Ghrelin, an endogenous ligand for GHS-R, has recently been purified from rat stomach. Although ghrelin is also expressed in the hypothalamus, the physiological significance of the ghrelin/GHS-R system is still unknown. We have created transgenic (Tg) rats expressing an antisense GHS-R mRNA under the control of the promoter for tyrosine hydroxylase (TH), thus selectively attenuating GHS-R protein expression in the Arc. Tg rats had lower body weight and less adipose tissue than did control rats. Daily food intake was reduced, and the stimulatory effect of GHS treatment on feeding was abolished in Tg rats. GH secretion and plasma insulin-like growth factor-I levels were reduced in female Tg rats. These results suggest that GHS-R in the Arc is involved in the regulation of GH secretion, food intake, and adiposity.

Diminished inibitory action of ethanol on the contraction of gallbladder isolated from chronically ethanol-fed Guinea pigs

Ethanol is known to decrease the gallbladder contractility. The purpose of this study was to clarify the mechanism of tolerance to the inhibitory action of ethanol on the gallbladder contractility. Male guinea pigs were fed ethanol (3%) or calorie-matched sucrose in the drinking water for 4 weeks. Then, the gallbladder was isolated, and its isometric tension was measured. The contractile responses to KCl, BAY K8644, histamine, and phorbol 12,13-dibutyrate in the normal medium were not different between the gallbladder strips from ethanol-fed and control guinea pigs. Ethanol at 25 mmol/l in vitro did not affect the contractile responses to KCl and BAY K8644 in the gallbladder strips from both ethanol-fed and control guinea pigs. On the other hand, ethanol at 25 mmol/l in vitro significantly inhibited the contractile responses to histamine and phorbol 12,13-dibutyrate in the gallbladder strips from the control guinea pigs, but it did not affect the contractile response to histamine and significantly augmented that to phorbol 12,13-dibutyrate in the strips from the ethanol-fed guinea pigs. Diphenhydramine, a selective H(1) receptor antagonist, abolished the histamine contraction in gallbladder strips from both control and ethanol-fed guinea pigs, while cimetidine, a selective H(2) receptor antagonist, did not affect histamine contraction, implying that histamine-induced contraction of guinea pig gallbladders is mediated only by H(1) receptors. Verapamil (1 micromol/l) completely inhibited the phorbol 12,13-dibutyrate-induced contraction of the strips from both ethanol-fed and control guinea pigs. The histamine-induced contraction was partly inhibited in the absence of Ca(2+) in the medium. In the gallbladder strips from both ethanol-fed and control guinea pigs, ethanol at 25 mmol/ in vitro did not affect the histamine-induced contraction in the absence of extracellular Ca(2+). Tolerance to the inhibitory action of ethanol developed selectively on contractile responses to histamine and phorbol 12,13-dibutyrate. Chronic ethanol administration produces tolerance to in vitro gallbladder contractility mediated by the Ca(2+) entry through L-type Ca(2+) channels linked with protein kinase C activation.

Chylomicronemia caused by lipoprotein lipase gene mutation related to a hyper-response of insulin secretion to glucose

A 39-year-old man with lipoprotein lipase (LPL) deficiency (height 177.7 cm, body weight 67 kg, and body mass index 21.2 kg/m2) showed severe hypertriglyceridemia (2,032 mg/dl). LPL activity and concentration were markedly low in postheparin plasma. LPL gene analysis revealed a homozygous mutation, Asp204 --> Glu in exon 5. Fasting plasma glucose (81 mg/dl) and insulin (2.7 microU/ml) levels were normal. Plasma glucose pattern during oral glucose (75 g) tolerance test was normal, however 30 minutes after glucose-loading the insulin secretion unexpectedly increased to 89.4 microU/ml. These data suggested that chylomicronemia might be related to a hyper-response of insulin secretion to glucose without obesity.

Extracellular pH affects platelet aggregation associated with modulation of store-operated Ca(2+) entry

The pH dependence of store-operated Ca(2+) influx (SOCI) into human platelets, as well as its physiological consequence, aggregation, was studied. In Ca(2+)-free medium, thapsigargin (1 microM) induced a small increase in intracellular free-Ca(2+) ([Ca(2+)](i)), which was not affected by changes in extracellular pH. The addition of Ca(2+) (0.5-3 mM) after Ca(2+) store depletion caused by thapsigargin resulted in concentration-dependent increases in [Ca(2+)](i) (SOCI), which were strongly inhibited by SKF-96365 (100 microM), an inhibitor of receptor-mediated Ca(2+) entry. SOCI was inhibited by acidosis (pH 6.9) and augmented by alkalosis (pH 7.9). The addition of Ca(2+) (0.5-3 mM) to platelets, which were kept in Ca(2+)-free medium, slightly but significantly increased [Ca(2+)](i). This Ca(2+) leak entry was also decreased and increased by extracellular acidosis (pH 6.9) and alkalosis (pH 7.9), respectively, but not affected by SKF-96365. Neither thapsigargin (1 microM) stimulation in Ca(2+)-free solution nor elevation of extracellular Ca(2+) alone was sufficient to induce platelet aggregation. In contrast, the addition of Ca(2+) (1 mM) to platelets activated by thapsigargin resulted in aggregation, which was markedly inhibited by SKF-96365 (100 microM). Platelet aggregation associated with SOCI was also inhibited by extracellular acidosis (pH 6.9) and augmented by extracellular alkalosis (pH 7.9). These results suggest that acidosis-induced inhibition, as well as alkalosis-induced promotion of platelet aggregation, involve pH effects on SOCI.

Nitric oxide-dependent and -independent inhibition by lipopolysaccharide of phosphoinositide hydrolysis in vascular smooth muscle

The present study was designed in order to clarify the mechanisms of diminished phosphoinositide (PI) hydrolysis by lipopolysaccharide (LPS) in blood vessels. In vitro pretreatment of rat aortic strips with LPS (1 microg/ml) for 10 or 24 hrs inhibited 5-hydroxytryptamine (5-HT, 100 microM)-induced inositol monophosphate accumulation in a time-dependent manner. Coincubation of the aortas with N(G)-monomethyl-L-arginine (LNMMA, 1 mM) completely prevented the early diminution of 5-HT-stimulated PI hydrolysis after 10-hr exposure to LPS but did not affect the delayed diminution after 24-hr exposure. Coincubation with cycloheximide (1 microM) did not prevent the delayed LPS-induced diminution of phosphoinositide hydrolysis. Tetraethylammonium (10 mM) did not restore the diminished phosphoinositide hydrolysis after 24-hr exposure to LPS, suggesting that the diminution is not due to K+ channel activation. Sodium fluoride (10 mM)-induced inositol monophosphate accumulation was also decreased in the aortic strips after LPS incubation for 24 hrs, and this decrease was not prevented by coincubation with LNMMA. LPS incubation time-dependently increased nitric oxide (NO) production in the aortas, which was completely inhibited by LNMMA or cycloheximide. These results suggest that NO is mainly involved in the inhibitory action of LPS on stimulated-PI hydrolysis in the early stage, while in the later stage, a factor(s) besides NO causes attenuation of the stimulated-PI hydrolysis.

Chronic central infusion of ghrelin increases hypothalamic neuropeptide Y and Agouti-related protein mRNA levels and body weight in rats

Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor (GHS-R), was originally purified from the rat stomach. Like the synthetic growth hormone secretagogues (GHSs), ghrelin specifically releases growth hormone (GH) after intravenous administration. Also consistent with the central actions of GHSs, ghrelin-immunoreactive cells were shown to be located in the hypothalamic arcuate nucleus as well as the stomach. Recently, we showed that a single central administration of ghrelin increased food intake and hypothalamic agouti-related protein (AGRP) gene expression in rodents, and the orexigenic effect of this peptide seems to be independent of its GH-releasing activity. However, the effect of chronic infusion of ghrelin on food consumption and body weight and their possible mechanisms have not been elucidated. In this study, we determined the effects of chronic intracerebroventricular treatment with ghrelin on metabolic factors and on neuropeptide genes that are expressed in hypothalamic neurons that have been previously shown to express the GHS-R and to regulate food consumption. Chronic central administration of rat ghrelin (1 microg/rat every 12 h for 72 h) significantly increased food intake and body weight. However, it did not affect plasma insulin, glucose, leptin, or GH concentrations. We also found that chronic central administration of ghrelin increased both neuropeptide Y (NPY) mRNA levels (151.0 +/- 10.1% of saline-treated controls; P < 0.05) and AGRP mRNA levels (160.0 +/- 22.5% of saline-treated controls; P < 0.05) in the arcuate nucleus. Thus, the primary hypothalamic targets of ghrelin are NPY/AGRP-containing neurons, and ghrelin is a newly discovered orexigenic peptide in the brain and stomach.

Intracellular alkalinization augments alpha(1)-adrenoceptor-mediated vasoconstriction by promotion of Ca(2+) entry through the non-L-type Ca(2+) channels

Modulation by intracellular pH of the vasoconstriction induced by alpha-adrenoceptor agonists was investigated in isolated guinea pig aorta. NH(4)Cl (15 mM) increased intracellular pH of aortic smooth muscle cells by about 0.2 pH unit and significantly augmented KCl-induced contraction of aortic strips, whereas simultaneous administration of NH(4)Cl (15 mM) plus Na(+) propionate (30 mM) failed to affect intracellular pH or contractility. NH(4)Cl (15 mM) potentiated contractions induced by alpha-adrenoceptor agonists, norepinephrine, phenylephrine and clonidine. Contraction induced by alpha(1)-selective adrenoceptor agonist, phenylephrine, but not that induced by norepinephrine or clonidine, was insensitive to inhibition by verapamil (1 microM). Phenylephrine-induced contraction was not affected by NH(4)Cl in Ca(2+)-free medium whereas extracellular Ca(2+)-induced contraction of phenylephrine-stimulated aorta was significantly augmented by NH(4)Cl. Consistently, 45Ca(2+)uptake into phenylephrine 1 microM)-stimulated aortic strips was increased by incubation with NH(4)Cl. The potentiating effects of NH(4)Cl on both phenylephrine-induced Ca(2+) entry and contraction were antagonized by Na(+) propionate. These results suggest that intracellular alkalinization facilitates alpha(1)-adrenoceptor-mediated vasoconstriction by facilitation of an agonist-induced Ca(2+) entry pathway that is independent of L-type Ca(2+) channels.

Acidosis inhibits gallbladder contraction mediated by protein kinase C activation

The effects of extracellular acidosis on gallbladder contraction were investigated using gallbladder strips isolated from guinea pigs. In an acidic medium (pH 6.9), gallbladder contraction induced by histamine and prostaglandin E2 was significantly lower than that in a normal medium (pH 7.4). Acidosis affected neither gallbladder contraction induced by histamine in the absence of extracellular Ca2+ nor that induced by KCl. Acidosis significantly inhibited Ca2+-induced contraction in the presence of sodium fluoride and phorbol 12,13-dibutyrate but not that in the presence of KCl. Staurosporine (30 nM) significantly inhibited gallbladder contraction induced by histamine and prostaglandin E2, but not that by KCl. Histamine-induced contraction in the presence of staurosporine was not affected by acidosis. Acidosis significantly inhibited Ca2+-induced contraction in the presence of histamine but not that in the presence of both histamine and staurosporine. These results suggest that extracellular acidosis selectively inhibits gallbladder contraction mediated by protein kinase C activation.

Cadmium accumulation augments contraction and phosphoinositide hydrolysis of vascular smooth muscles

Effects of cadmium accumulation in blood vessels on vasoconstriction and hydrolysis of phosphoinositides were investigated using aortas isolated from rats. The aortic strips were incubated with cadmium chloride (10 microM) for 24 hr and then washed out (cadmium accumulation). In the cadmium-accumulated aortas, contractile responses to KCl and 5-hydroxytryptamine were augmented compared to the control incubated with a vehicle. The degree of the augmentation by cadmium was higher in 5-hydroxytryptamine contraction than in KCl contraction. The level of 5-hydroxytryptamine-induced contraction relative to KCl-induced contraction (expressed as percent of maximum KCl contraction in each strip) was also significantly increased in the cadmium-accumulated aortas as compared to the control. Cadmium pretreatment augmented 5-hydroxytryptamine-stimulated inositol monophosphate accumulation, while there was no difference in the basal level of inositol monophosphate between the cadmium-accumulated aortas and the control. These results suggest that cadmium accumulation increases vasocontractility, in part because of the facilitation of phosphoinositide hydrolysis.

Daunorubicin inhibits gene expression of cyclooxygenase-2 in vascular smooth muscle cells

Daunorubicin (0.1-1 microM) concentration-dependently inhibited prostacyclin production induced by interleukin-1beta (IL-1beta, 2.5 ng/ml) in cultured aortic smooth muscle cells isolated from rats. IL-1beta stimulation caused activation of nuclear factor-kappaB (NF-kappaB) and expression of cyclooxygenase-2 (COX-2) mRNA and protein, which were inhibited by daunorubicin. However, COX activity, evaluated by conversion of exogenous arachidonic acid to prostacyclin, was not affected by daunorubicin (0.1-1 microM). Protein expression of COX-1 and NF-kappaB was not affected by daunorubicin. Daunorubicin also inhibited nitric oxide (NO) production induced by IL-1beta. These results suggest that daunorubicin attenuated prostacyclin synthesis through inhibiting expression of COX-2 mRNA, which could be explained by perturbation of NF-kappaB activation.

Range of motion after Bankart repair. Vertical compared with horizontal capsulotomy

We studied the range of shoulder motion of patients who underwent vertical as compared with horizontal capsulotomies during open Bankart repair for recurrent anterior dislocations of the shoulder. A vertical capsulotomy was used in 10 shoulders and a horizontal capsulotomy was used in 14 shoulders. Except for the method of capsulotomy, the surgical procedure and postoperative rehabilitation were the same. The range of motion was measured at 1.5, 2, 3, 4, 5, 6, 9, and 12 months after the surgery, and at the final follow-up (average, 49 months for the vertical and 26 months for the horizontal group). No dislocations recurred, and the anterior apprehension test was negative in all of the patients in both groups. External rotation in abduction was greater in the horizontal group than in the vertical group; the differences were significantly greater at 9 months and 12 months after surgery and at the final follow-up. External rotation in adduction, flexion, and internal rotation were not significantly different between the groups. We conclude that Bankart repair through a horizontal capsulotomy preserves a better range of external rotation in abduction than does a vertical approach.

Position of immobilization after dislocation of the glenohumeral joint. A study with use of magnetic resonance imaging

BACKGROUND

Glenohumeral dislocations often recur, probably because a Bankart lesion does not heal sufficiently during the period of immobilization. Using magnetic resonance imaging, we assessed the position of the Bankart lesion, with the arm in internal and external rotation, in shoulders that had had a dislocation.

METHODS

Coaptation of a Bankart lesion was examined with use of magnetic resonance imaging, with the arm held at the side of the trunk and positioned first in internal rotation (mean, 29 degrees) and then in external rotation (mean, 35 degrees), in nineteen shoulders. Six shoulders (six patients) had had an initial anterior dislocation, and thirteen shoulders (twelve patients) had had recurrent anterior dislocation. Fast-spin-echo T2-weighted axial images were made when the dislocation had occurred less than two weeks earlier, and spin-echo T1-weighted axial images after intra-articular injection of gadolinium-diethylenetriamine pentaacetic acid were made when the dislocation had occurred more than two weeks earlier. Separation and displacement of the anteroinferior portion of the labrum from the glenoid rim were measured on the axial images, and coaptation of the anterior part of the capsule to the glenoid neck was assessed by measurement of the detached area, opening angle, and detached length.

RESULTS

Separation and displacement of the labrum were both significantly less (p = 0.0047 and p = 0.0017, respectively) when the arm was in external rotation than when it was in internal rotation. The detached area and the opening angle of the anteroinferior portion of the capsule were both significantly smaller (p = 0.0003 and p < 0.0001, respectively), and the detached length was significantly shorter (p < 0.0001) with the arm in external rotation.

CONCLUSION

Immobilization of the arm in external rotation better approximates the Bankart lesion to the glenoid neck than does the conventional position of internal rotation.

Thyroid hormones regulate pituitary growth hormone secretagogue receptor gene expression

Thyroid hormones regulate growth hormone (GH) secretion by actions both at the hypothalamus and at the pituitary gland. At the level of the pituitary, thyroid hormones increase GH and GH-releasing hormone receptor (GHRH-R) mRNA expression. To test if thyroid hormones might also regulate the pituitary expression of mRNA for the recently identified GH secretagogue (GHS) receptor, GHS-R, primary pituitary cell cultures from adult male rats were treated with triiodothyronine (T3) and GHS-R mRNA levels were assessed by reverse transcriptase-polymerase chain reaction. T3 increased pituitary GHS-R mRNA levels in a dose- and time-dependent manner. The stimulatory action of T3 on GHS-R mRNA levels was also observed in the presence of the RNA synthesis inhibitor, actinomycin D, indicating that gene transcription is not required. Closer examination of the decay rates of GHS-R mRNA in the presence of actinomycin D revealed T3 extended the half-life of the GHS-R mRNA from 8 h (basal) to15 h, demonstrating that T3 increases GHS-R mRNA levels in vitro by increasing message stability.

Estrogen receptor (ER)alpha, but not ERbeta, gene is expressed in growth hormone-releasing hormone neurons of the male rat hypothalamus

GH synthesis and release from pituitary somatotropes is controlled by the opposing actions of the hypothalamic neuropeptides, GH-releasing hormone (GHRH), and somatostatin (SS). There is a striking sex difference in the pattern of GH secretion in rats. Early reports indicate that gonadal steroids have important imprinting effects during the neonatal period. Recently, our laboratory and others have reported that the GH secretory pattern is altered by short-term gonadal steroid treatment in adult rat, suggesting that gonadal steroids are also important determinants of the pattern of GH secretion during adult life. However, the site of action of gonadal steroids in the adult rat hypothalamus is still unknown. In this study, we used in situ hybridization in the adult male rat brain to determine whether GHRH neurons and/or SS neurons coexpress estrogen receptor alpha (ERalpha) and ERss genes. In the medial basal hypothalamus of adult male rat, the ERalpha messenger RNA (mRNA) was located in medial preoptic area (MPA) and arcuate nucleus (ARC), whereas ERss mRNA was detected in MPA, supraoptic nucleus, and paraventricular nucleus. From studies using adjacent sections, the distribution of ERalpha mRNA-containing cells appeared to overlap in part with those of GHRH and SS expressing cells only in the ARC. On the other hand, the distribution of ERss mRNA-containing cells does not appear to overlap with GHRH cells or SS cells. The double label in situ hybridization studies showed that in the ARC, 70% of GHRH neurons contain ERalpha mRNA, whereas less than 5% of SS neurons expressed the ERalpha gene. These results indicated that GHRH neurons are direct target cells for estrogens, and estrogens may act directly on GHRH neurons through ERalpha during adult life to modify GH secretory patterns.

Generation of polyclonal antiserum against the growth hormone secretagogue receptor (GHS-R): evidence that the GHS-R exists in the hypothalamus, pituitary and stomach of rats

Growth hormone (GH) secretagogues (GHSs), which stimulate GH secretion, are synthetic compounds that act through the GHS receptor (GHS-R) which has been recently cloned. We raised an antiserum in a rabbit against a synthetic peptide corresponding to amino acid residues 248-260 of the third intracellular loop of the rat GHS-R. A competitive immunoassay showed that the antiserum had a specific affinity for the target peptide. To confirm the specificity of the antiserum, the GHS-R cDNA was stably expressed in COS-7 cells. In Western blot analysis, the band was detected at 44 kDa in the extracts from COS-7 cells expressing GHS-R (COS-7/tf3-2) but not in those from wild-type COS-7 cells. Furthermore, while COS-7/tf3-2 cells were strongly immunostained for GHS-R, no GHS-R-like immunoreactivity was observed in wild-type COS-7 cells. Immunoreactive bands were also observed at approximately 46 kDa in the extracts from rat hypothalamus, pituitary and stomach by Western blot analysis. These studies are the first to show the existence of GHS-R protein in the stomach. The antiserum for the GHS-R is sensitive and specific, and it would be useful for clarifying the roles of GHS/ghrelin.

[Effects of ethanol on the nervous and vascular systems: the mechanisms of alcohol-induced hypertension]

Many previous experimental and epidemiological studies have shown that alcohol consumption has a positive correlation with the incidence of hypertension. The effects of ethanol on the nervous and vascular systems in relation to the mechanisms of alcohol-induced hypertension proposed so far are reviewed here. Alcohol ingestion influences many pathophysiological functions which regulate blood pressure, as follows: 1) Sympathetic nervous activity is increased after drinking. 2) Ethanol acts directly on the contractility of vascular smooth muscle. Ethanol acutely contracts some arteries and increases their contractile responses to agonists, while it also displays inhibitory effects on vasocontractility in other arteries. Thus, ethanol has two opposite actions, both of which depend on the kinds of vessels and animal species used for the experiments. Intra- and extracellular Ca2+ mobilization and activation of the contractile apparatus have been suggested as mechanisms for ethanol's vasocontractile actions. 3) Chronic alcohol ingestion has been reported to induce a deficiency of blood and intracellular magnesium, which influences cellular Ca2+ homeostasis through attenuation of plasmalemmal ATPase activity. Direct alcohol effects on cardiovascular systems may not be involved in hypertension that develops after long-term habitual drinking. 4) Ethanol affects vascular endothelial functions, inhibiting endothelial NO- and EDHF-dependent vasorelaxations. 5) The serum levels of vasoactive substances such as cathecolamines, renin-aldosterone, prostacyclin, and endothelin have been reported to be affected by alcohol ingestion or ethanol in vitro. 6) In heavy drinkers, alcohol withdrawal results in an elevation of blood pressure due to sympathetic nervous stimulation. 7) Long-term heavy drinking often results in the development of insulin resistance and glucose intolerance, which in turn triggers hypertension. 8) The difference in the genetic polymorphism of acetaldehyde dehydrogenase among Japanese people may not be directly related to development of alcohol-induced hypertension. As mentioned above, alcohol shows multiple actions on various factors regulating blood pressure. More detailed and integrated mechanisms for alcohol-induced hypertension, which is not a homogeneous disease, remain to be clarified.

A rare anatomic variant of the superior glenohumeral ligament

The attachment of the superior glenohumeral ligament (SGHL) to the upper pole of the glenoid is variable and 3 types have been described. We report an anatomic variant of SGHL attachment to the upper pole of the glenoid that has not heretofore been reported in the literature. In this case, the SGHL overrode the biceps origin, continued to the superior labrum posteriorly, and had no attachment to the middle glenohumeral ligament or the anterior labrum. This variant was detected during routine arthroscopic examination undertaken before surgery on a rotator cuff tear.

Tyrosine phosphorylation increases Ca2+ sensitivity of vascular smooth muscle contraction

In order to elucidate the role of tyrosine phosphorylation in vasoconstriction, we investigated the effects of inhibitors of tyrosine kinase (genistein, 30 microM) and phosphatase (sodium o-vanadate, 5 microM) on the contraction of aorta isolated from guinea pig. Genistein significantly inhibited norepinephrine-induced contraction, but it did not affect that induced by KCI. Thus, tyrosine phosphorylation may not be involved in the contractile response to KCI alone. The aortic contraction elicited by KCl was significantly augmented by sodium o-vanadate, which increased both the maximum force and pD2 values of KCl contraction. In the presence of verapamil, KCl-induced contraction was abolished even after pretreatment with sodium o-vanadate. Sodium o-vanadate also augmented Ca2+-induced contraction in the aortic strips depolarized with KCl, increasing both its maximum force and pD2 values. Neither basal 45Ca2+ uptake nor verapamil-sensitive 45Ca2+ uptake induced by KCl were affected by pretreatment with sodium o-vanadate. These results suggest that tyrosine phosphorylation is involved in the contraction of guinea-pig aorta not through transplasmalemmal Ca2+ entry but through increased Ca2+ sensitivity of the intracellular contractile pathway.

The hexapeptide KP-102 (D-ala-D-beta-Nal-ala-trp-D-phe-lys-NH(2)) stimulates growth hormone release in a cichlid fish (Ooreochromis mossambicus)

Abstract Studies in mammals have shown that synthetic Met-enkephalin derivatives, called growth hormone-releasing peptides (GHRPs), stimulate growth hormone (GH) release. The present study was conducted to determine whether the GHRP, KP-102, specifically stimulates GH release in a teleost. Tilapia (Oreochromis mossambicus) were given a single intraperitoneal injection of KP-102 (D-Ala-D-beta;-Nal-Ala-Trp-D-Phe-Lys-NH(2)) or bovine GHRH(1-29)-amide or vehicle and blood was sampled at 1, 6 and 12 h after injection. KP-102 was administered at two doses of 1 ng/g and 10 ng/g body weight, whereas GHRH (positive control) was administered at a single dose of 10 ng/g body weight. Plasma levels of tilapia GH and prolactins (tPRL(177) and tPRL(188)) were determined by radioimmunoassay. As expected, GHRH injection significantly (P<0.001) elevated plasma GH levels (ng/ml) in tilapia at 6 h post-injection. KP-102 also significantly elevated GH levels (at the low dose) at 6 (P<0.05) and 12 (P<0.01) hours post-injection. There were no significant effects on plasma PRL(s) levels, although mean levels of both PRLs were elevated at 6 h post-injection. These results show for the first time that GHRPs stimulate GH release in teleosts and suggest that the GHRP receptor and possibly a "Ghrelin-like" ligand are also present in lower vertebrates.

Central effect of ghrelin, an endogenous growth hormone secretagogue, on hypothalamic peptide gene expression

Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor (GHS-R), was originally purified from the rat stomach. Like the synthetic GHSs, ghrelin specifically releases GH following intravenous administration. Also consistent with the central actions of GHSs, ghrelin-immunoreactive cells were shown to be located in the hypothalamic arcuate nucleus as well as the stomach. However, the central actions of ghrelin have not been elucidated. Here, we used radioactive in situ hybridization histochemistry to examine the effects of central administration of rat ghrelin on neuropeptide genes that are expressed in hypothalamic neurons that were previously shown to express GHS-R. We found that central administration of ghrelin increased both agouti-related protein (AGRP) mRNA levels (245.8 +/- 28.3% of the saline-treated controls; p < 0.01) in the hypothalamus and food intake (5.7 +/- 0.9 g ghrelin vs. 1.9 +/- 0.5 g saline; p < 0.05). On the other hand, 1 microg of rat ghrelin central administration did not alter the episodic GH release of freely moving adult male rats. Thus, ghrelin has an alternative role in stimulating food intake via an increase of AGRP rather than the release of GH from the pituitary.

Disturbed expression of the anti-apoptosis gene, survivin, and EPR-1 in hematological malignancies

Survivin is a newly discovered inhibitor of the apoptosis protein, IAP, expressed during development and in human cancers. The effector cell protease receptor-1 (EPR-1) gene is oriented in the opposite direction on the same DNA double strand. Thus, the Survivin and EPR-1 (Survivin/EPR-1) genes exist in a head-to-head configuration. It is not clear whether mutual expression of the Survivin/EPR-1 genes occurs in both normal cells and cancer cells. Here, we investigated the mutual expression of the Survivin/EPR-1 genes in 12 normal peripheral blood (PB) specimens, seven normal bone marrow (BM) specimens, five lymph node (LN) specimens, and seven leukemic cell lines, and 27 patients with malignant lymphoma (ML), four with acute lymphocytic leukemia (ALL), three with acute myelocytic leukemia (AML), and four with chronic myelocytic leukemia in blastic crisis (CML-BC). Using Northern blot analysis, small amounts of EPR-1 mRNA were detected in normal PB, normal BM and LN specimens, but no Survivin mRNA was detected. However, Survivin mRNA was detected in two of the 12 normal PB, six of the seven normal BM and one of the five LN specimens using reverse transcription and polymerase chain reaction (RT-PCR). Expression of both the Survivin and EPR-1 genes was detected in six of the seven cell line samples by Northern blot, and in all of them by RT-PCR. Mutual expression of the Survivin and EPR-1 genes was detected in three of the four CML-BC samples, 15 of the 27 ML samples, two of the four ALL samples, and all three AML samples using the RT-PCR method. No EPR-1 expression with or without Survivin expression was clearly detected in eight of the nine diffuse large B-cell lymphoma (DLB) specimens, two of the six follicular center lymphoma specimens, one of the four specimens of nodular sclerosis of Hodgkin's lymphoma, two of the four ALL specimens or one of the four CML-BC specimens. The data presented here show that disrupted expression of the Survivin/EPR-1 genes occurred in many kinds of hematologically malignant cells. This may be of biological importance.

Wogonin inhibits inducible prostaglandin E(2) production in macrophages

Effects of 5,7-dihydroxy-8-methoxyflavone (wogonin) on cyclooxygenase-2 (COX-2)-mediated prostaglandin E(2) production in macrophages were investigated. Stimulation with lipopolysaccharide (LPS; 1 microg/ml) greatly increased prostaglandin E(2) production in RAW 264.7 murine macrophages. The stimulated prostaglandin E(2) production was abolished in the presence of indomethacin (1 microM) or cycloheximide (2 microM), suggesting that the increased production of prostaglandin E(2) by LPS reflects the inducible synthesis of prostaglandin E(2) by COX-2. Wogonin (0.1-50 microM) concentration-dependently inhibited inducible prostaglandin E(2) production. Wogonin at concentrations as low as 0.5 microM directly attenuated enzymatic activity of COX-2. The protein expression of COX-2 was depressed by wogonin at concentrations of 10 microM and more. These results suggest that wogonin decreases inducible prostaglandin E(2) production in macrophages by inhibiting both COX-2 activity and COX-2 expression. The former action requires much lower doses of wogonin. These wogonin actions may explain, in part, its anti-inflammatory action.

Selective corticotropin-releasing factor type 1 receptor antagonist blocks conditioned fear-induced release of noradrenaline in the hypothalamic paraventricular nucleus of rats

The effects of conditioned fear on the release of noradrenaline in the hypothalamic paraventricular nucleus (PVN) and the involvement of corticotropin-releasing factor (CRF) receptor type 1 (CRFR1) in conditioned fear-induced changes in noradrenaline release were examined by intracerebral microdialysis in rats. Conditioned fear was produced by placing animals into a box where they had previously been exposed to a 5-min period of electric footshock, 135 min prior to the start of experiment. Conditioned fear for 20 min produced a significant increase in the release of noradrenaline in the PVN. Intraperitoneal preadministration of a selective nonpeptidic CRFR1 antagonist, CRA1000, completely blocked the conditioned fear-induced release of noradrenaline. These results suggest that CRFR1 is involved in the release of noradrenaline in the hypothalamic PVN induced by conditioned fear.

A subpopulation of fibroblast growth factor-2-binding heparan sulfate is lost in human papillary thyroid carcinomas

We hypothesized that a change in composition of proteoglycans can regulate the bioactivity of fibroblast growth factor (FGF)-2 in the thyroid. In order to test this hypothesis, we established a simple and sensitive method for detecting FGF-2-binding heparan sulfates and characterized them in papillary thyroid carcinomas and normal thyroids. The thyroid extracts were applied to a Q-Sepharose anion exchange column. After the column was washed with 10 mM of phosphate buffer, 1 microgram of human recombinant FGF-2 was added onto the column. The column was eluted with a gradient of NaCl (0.3-1.5 M). Each fraction was blotted onto nitrocellulose membrane. Immunoreactivity of heparan sulfate and FGF-2 was revealed by the incubation of membranes with the specific antibodies, and quantitatively estimated by measuring the density of the color product. In normal thyroids, immunoreactivity of heparan sulfate was detected as two peaks at 0.7 and 0.9 M of NaCl. Heparan sulfate-containing fractions also showed FGF-2 immunoreactivity, indicating the complex formation of FGF-2 and heparan sulfate. In papillary thyroid carcinomas, immunoreactivity of heparan sulfate showed various elution profiles on Q-Sepharose chromatography, including single peak at 0.7 M of NaCl and the one similar to that of the normal thyroids. However, FGF-2 immunoreactivity was detected only in the fractions eluting at 0.7 M of NaCl. This loss of a subpopulation of FGF-2-binding heparan sulfate in human papillary thyroid carcinomas may lead to the increase of free FGF-2 bioavailable in extracellular matrix.

Response of leptin mRNA to 24-h food deprivation and refeeding is influenced by age in rats

To obtain an insight into the influence of aging on leptin gene expression, the responses of leptin mRNA in retroperitoneal and epididymal adipose tissues and plasma leptin concentrations to 24-h food deprivation and refeeding were examined in 2-, 10- and 24-month-old normal rats. The basal level of leptin gene expression in retroperitoneal adipose tissue was significantly higher in 10- and 24-month-old rats than that in 2-month-old rats, while the level in epididymal adipose tissue was highest in 10-month-old rats for all three age groups. The basal concentrations of plasma leptin was significantly higher in 10- and 24-month-old rats than those in 2-month-old rats. The 24-h food deprivation was followed by a significant reduction in leptin mRNA expression in both retorperitoneal and epididymal adipose tissues for all three age groups. The leptin gene expression was restored to control levels 24 h following refeeding in the 2- and 10-month-old rats, but failed to be restored in the 24-month-old rats. In addition, the time course of recovery for leptin mRNA expression by refeeding to the control levels differed between the retroperitoneal and the epididymal adipose tissue in 2- and 10-month-old rats. The concentrations of plasma leptin 24 h following refeeding were compatible with the leptin mRNA levels in adipose tissues in three age groups. These results suggest that the expression of the leptin gene in response to food-deprivation and refeeding is influenced by an animal's age and that this expression is different for different regions of white adipose tissue.

Age-related change in relationship between body-mass index, serum sialic acid, and atherogenic risk factors

In order to clarify the significance of obesity in atherosclerotic risk at different ages, the relationship between the body-mass index, serum sialic acid concentration, and various atherosclerotic risk factors were investigated for healthy subjects in three different age groups, 35-39, 40-49 and 50-59 years old. The body-mass index correlated significantly with mean arterial blood pressure, fasting blood sugar, serum triglycerides, atherogenic index and serum uric acid in all age groups. The magnitudes of the association of body-mass index with mean arterial blood pressure, fasting blood sugar and serum triglycerides decreased with age, while those of the association with atherogenic index and serum uric acid were not different among the three age groups. Body-mass index did not show significant correlation with white blood cell count, platelet count or smoking in any of the age groups. Simple and multiple regression analyses showed that body-mass index was significantly correlated with serum sialic acid in the 35-39-year-old group, but not in the other two groups. Neither the percentage of obese subjects (body-mass index > 26.4) nor the mean values of body-mass index were different among the three groups. These results suggest that for younger people, the body-mass index is related more closely with some atherosclerotic risk factors (e.g. blood pressure, blood sugar and serum triglycerides), and obesity may be possibly more involved in the progression of atherosclerosis, compared to more elderly people.

Glucocorticoids regulate pituitary growth hormone secretagogue receptor gene expression

Glucocorticoids regulate growth hormone (GH) secretion by modulating both hypothalamic and pituitary function. At the level of the pituitary, glucocorticoids increase GH and GH-releasing hormone receptor (GHRH-R) gene expression. To test if glucocorticoids might also regulate the pituitary expression of the recently identified GH secretagogue (GHS) receptor, GHS-R; adult male rats were adrenalectomized or sham operated, and treated with the synthetic glucocorticoid (dexamethasone, 200 microg/day) or vehicle for 8 days. Pituitary GHS-R mRNA levels were assessed by reverse transcriptase polymerase chain reaction (RT-PCR). Adrenalectomy decreased pituitary GHS-R mRNA to 45% of vehicle-treated, sham-operated rats (P < 0.05). Administration of dexamethasone increased GHS-R mRNA levels in sham-operated as well as in adrenalectomized rats (199 +/- 24% (P < 0.05) and 369 +/- 48% (P < 0.01) of vehicle-treated controls). Addition of dexamethasone to primary rat pituitary cell cultures increased GHS-R mRNA levels in a dose- and time-dependent manner while the transcriptional inhibitor, actinomycin D, completely blocked the stimulatory action of dexamethasone. Taken together, these results suggest glucocorticoids directly increase pituitary GHS-R mRNA levels by stimulating GHS-R gene transcription.

Thickening of the roentgenometrical gastric fold in the elderly: relation to peptic ulcer incidence

Radiographic upper gastrointestinal barium examination is commonly used to diagnose peptic ulcer. However, little attention has been paid to its thickening, except in Ménétrier disease and gastric carcinoma of Borrman type IV. The present study was undertaken to investigate the relation of age to roentgenometrical gastric fold width and history of peptic ulcer. The subjects were 724 men (35-64 years old) who participated in a periodic medical health examination and underwent radiographic upper gastrointestinal barium examination. The gastric fold width of the anterior wall in the body was evaluated by air-contrast examination and expressed in millimeters. In the group with a history of peptic ulcer, the roentgenometrical gastric fold was significantly thicker than that in the group without it. The fold width was significantly greater in the elderly group (55-64 years old) than in the young (35-44 years old) and middle-aged (45-54 years old) groups. The fold width tended to increase with age in persons with peptic ulcer history, but not in those without it. When the subjects were divided into three groups by gastric fold width, the incidence of peptic ulcer was significantly higher in the upper third group compared with the lower third group. This relationship between the gastric fold width and the incidence of peptic ulcer tends to become stronger with aging. In the heavy smoker group (> or = 10 of cigarettes per day), the gastric fold width was significantly thicker than that of non-smokers or those who smoked less. This relationship also tended to grow stronger with aging. The mean incidence of peptic ulcers was significantly higher among the heavy smokers. However, daily alcohol drinkers did not show any significant difference in gastric fold width from the other subjects. The gastric fold seems to be thicker in persons with peptic ulcer history, and the incidence of peptic ulcer is higher in persons with thicker gastric fold. These relationships tend to grow stronger with aging.a

Masculinizing effect of dihydrotestosterone on growth hormone secretion is inhibited in ovariectomized rats with anterolateral deafferentation of the medial basal hypothalamus or in intact female rats

There is a striking sex difference in the pattern of growth hormone (GH) secretion in rats. Our previous studies showed that short-term administration of pharmacological doses of testosterone or dihydrotestosterone (DHT) masculinized the GH secretory pattern in ovariectomized (OVX) rats. The locus where testosterone or DHT interacts with the somatotropic axis is believed to be the hypothalamus. To obtain insights into this phenomenon, we administered a single dose of DHT s.c. to adult OVX rats at 0.01, 0. 1 or 1 mg/rat. Blood GH concentrations were measured in unanaesthetized rats. Six to 12 h after the s.c. administration of all three doses of DHT, the GH secretory pattern revealed a male-like secretory pattern as shown by episodic bursts occurring at 2-3-h intervals with low or undetectable trough levels. When anterolateral deafferentation of the medial basal hypothalamus (ALC) was performed, the blood concentrations revealed irregularly occurring small fluctuations, instead of the usual high bursts, but the basal GH concentration was significantly higher than that of OVX-sham-operated rats. DHT treatment did not elicit pulsatile GH secretion or alter GH concentrations in OVX rats with ALC. When intact adult female rats received DHT at a dose of 1 mg/rat, the male-like GH secretory pattern was not induced. These results suggest that neural inputs from the anterolateral direction to the medial basal hypothalamus are necessary for the masculinizing effect of DHT on the GH secretory pattern in OVX rats, and that oestrogen in intact female rats prevents the masculinizing effect of DHT.