In order to understand the physiological role of endogenous insulin or glucagon in somatostatin release, isolated rat pancreatic islets were treated with antiinsulin or antiglucagon antiserum in the presence of physiological amounts of glucose.
The release of somatostatin was unchanged by treatment with antiinsulin antiserum which neutralized insulin released by 3.3, 8.3 and 16.7 mM of glucose. However, somatostatin release after treatment with antiglucagon antiserum was much reduced at all concentrations of glucose when compared with the release from control serum.
Exogenous rat insulin (0.11, 1.11μg/ml) had no effect, but exogenous glucagon (1, 5μg/ml) resulted in a significant increase.
Somatostatin release was stimulated by glucose, but the effect was insignificant.
These results clearly indicate the physiological role of endogenous glucagon in the modulation of somatostatin release from the islets of Langerhans. Furthermore, the physiological relationship between A, B and D cells may be mediated through the paracrine mechanism.

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In order to clarify the pancreatic endocrine functions in mild chronic pancreatitis, the response of insulin to oral glucose load and the response of glucagon and human pancreatic polypeptide (HPP) to insulin-induced hypoglycemia were investigated in five normal controls and eight patients with chronic pancreatitis but without diabetes mellitus. Although insulin and glucagon responses in patients with chronic pancreatitis tended to be lower than those in normal subjects, the differences between the two groups were not statistically significant. In contrast, HPP response to hypoglycemia in the patients was markedly impaired and significantly lower than that in normals (p<0.02).
This finding indicates that the impairment of HPP response is the earliest and most definite manifestation among pancreatic endocrine abnormalities in chronic pancreatitis.

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A sandwich-type enzyme immunoassay for human chorionic gonadotropin (hCG) was developed with anti hCG-β antibody-enzyme complex and the immobilized solidphase antibody which was prepared from the antiserum to the synthetic peptide corresponding to the carboxyl-terminal region of the β-subnit of hCG (hCG-β).
This assay system showed a high sensitivity equal to the radioimmunoassay and did not cross-react with human luteinizing hormone (hLH), human folicle stimulating hormone (hFSH) or β-subunit of hCG (hCG-β).
The coefficients of variation in within-run and between-run were less than 10% and there was a good correlation between the enzyme immunoassay and the radioimmunoassay of serum sample with a regression eqnation of y=1.038×-0.647 and a correlation coefficient of r=0.953.

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Plasma samples were obtained by repeated venopunctures immediately before, and at 15, 30, 60, 120 and 180 min after intravenous bolus administration of 100μg synthetic LH-RH in normal and various anovulatory women. Plasma hLH levels were determind by an in vitro bioassay and a radioimmunoassay with improved reagents. The LH-RH stimulation induced an abrupt elevation of both biological and immunological hLH activities in normal and anovulatory women, although the responsiveness to LH-RH differed from case to case. Both elevated biological and immunological hLH activities decreased gradually with a half disappearance time of 122.4±27.9 min and 112.5±25.4 min, respectively (Mean±S. D.). A transient and significant depression in the ratio of biological to immunological hLH activities (B/I ratio) was observed at 15 min after the LH-RH administration in normal subjects. This depression is attributable to the cross-contamination of an increased amount of hLH subunits induced by LH-RH stimulation. The B/I ratios were significantly elevated throughout the investigation period in the anovulatory patients when compared with those in the normal subjects. This elevation appears to indicate the increased discharge of special type (s) of hLH subpopulations of high biological potency in the anovulatory cases.

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In order to systematically analyze the regulation and metabolism of steroid hormones in a case of primary aldosteronism with multiple lesions, including adenoma and nodular hyperplasia of the left adrenal gland, the amounts of 9 steroids (progesterone (P), 11-deoxycorticosterone (DOC), corticosterone (B), 18-hydroxycorticosterone (18-OH-B), aldosterone (Aldo), 17α-hydroxyprogesterone (17-OH-P), 11-deoxycortisol (S), cortisol (F) and dehydroepiandrosterone sulfate (DHEAS)) contained in the plasma and in the adrenal tissues were measured.
The patient (a 39-year-old female) was admitted to our hospital because of hypokalemia and hypertension. A diagnosis of primary aldosteronism was made on the basis of a complete evaluation, and an adenoma (1.8×1.2 cm), a nodular hyperplasia (0.5×0.5 cm), a microadenoma and a cortical nodule were found on the left adrenal gland.
In vivo studies revealed that the plasma level of Aldo was high, but those of the other steroid hormones were within the normal range. After ACTH infusion, the plasma levels of the 9 steroid hormones increased by 2 to 17 times the base levels.
In particular, the responses of DOC and B were markedly high.
In vitro studies on P, DOC, B, Aldo and F content in the adenoma (A), the nodular hyperplasia (A), the adjacent adrenal tissue (C) and the right normal adrenal tissue (D) revealed that, except for F, they were highest in A, followed by A, D and C in that order.
In incubation studies with ACTH using A and C, it was found that the levels of 8 steroid hormones with the exception of DHEAS were higher in A than in C.
In particular, the response of B in A was markedly increased.
These findings suggest that aldosteronoma produces 8 steroid hormones under conditions of excess ACTH, while at physiological levels of ACTH, it produces only Aldo in excess.

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The influences of bile-duct obstruction upon basal plasma glucagon levels and the relationships between glucagon-like substance in bile and postobstructive plasma glucagon were examined in the rabbit. Immunoreactive glucagon (IRG) was measured with antiserum 30 K (Unger).
Bile-duct obstruction was followed by a prompt rise within 60 minutes in plasma IRG which was four times the basal value, but had little influence on plasma immunoreactive insulin and blood sugar.
The biliary IRG and the elevated plasma IRG during bile-duct obstruction were filtrated with a Bio-Gel P-10 column. Most of the postobstructive plasma IRG appeared in the void volume area (plasma large IRG), while almost all of the biliary IRG was recovered in the position equivalent to approximately 2000 daltons (biliary IRG 2000). Both IRGs of different molecular sizes revealed similar dilution curves in radioimmunoassay to that with porcine glucagon.
After incubation of bile with preobstructive plasma, the IRG elution profile of the mixture contained an increased amount of large molecular size IRG similar to that of postobstructive plasma in regard to 30K specificity and elution position. The disappearance of IRG in the void volume area was observed when the bile-plasma mixture or the postobstructive plasma was filtrated with acidic buffer.
These results suggest that plasma large IRG contributing to hyperglucagonemia during bile-duct obstruction may be derived from biliary IRG 2000.

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The effect of calcitonin (CT) on hepatic glycogenolysis was investigated after a single subcutaneous administration of the hormone to intact rats. Amdinistration of CT (porcine CT; 80 MRC mU/100g BW) produced a significant decrease in glycogen content of the liver, and corresponding increases in phosphorylase a activity and calcium content of the particulate glycogen fraction in the liver. These alterations were observed with the dose of CT at physiological level. The removal of calcium by 1 mM EGTA treatment of the hepatic particulate glycogen caused a clear reduction in the increase in phosphorylase a activity produced by CT administration. Meanwhile, the enzyme activity in 1 mM EGTA-treated particulate glycogen of the liver in both control and CT (80 MRC mU/100g BW)-treated rats was significantly enhanced by the addition of calcium ion (10μM). Furthermore, a single intraperitoneal administration of calcium chloride (2.0 mg Ca/100g BW) to intact rats produced α remarkable increase in phosphorylase a activity and calcium content of the hepatic glycogen particulate fraction. These results suggest that the promotion of hepatic glycogenolysis by CT administration may result from the increase in phosphorylase α activity mediated by cellular calcium.

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We studied the effect of acute short-term exercise on insulin binding to erythrocytes in patients with non-insulin dependent diabetes mellitus and normal controls. In the normal controls, insulin binding was increased immediately after the exercise and returned to the basal level at 30 min after the exercise. This increase was due to an affinity change without any change in the insulin receptor number. In contrast, insulin binding tended to decrease in the diabetics after the exercise, and this change was due to a decreased affinity without any change in the number of insulin receptors. These results indicate that the control mechanism of insulin receptor affinity in response to exercise is different in non-insulin dependent diabetics and normals.

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We have examined the binding of 44% saponin from Panax ginseng, and extracts from Eleuthrococcus senticosus (Siberian ginseng) to classical steroid receptors in vitro. Both extracts had demonstrable affinity for progestin, mineralocorticoid and glucocorticoid receptors; the Siberian ginseng also bound to estrogen receptors. Highest affinity binding was to glucocorticoid receptors, with an approximate Ki of 8×10^-6M for Panax ginseng. Such interactions may explain the reported glucocorticoid-like effects of ginseng in vivo.

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This aim of this study was to determine whether RBC insulin receptor assay represents a clinically useful way of assessing insulin sensitivity in obes children. Steady state plasma glucose (SSPG) was established by a constant infusion of glucose (6 mg/kg/min), insulin (0.8 mU/kg/min) and somatostatin (125μg/m²/h), following the loading dose of somatostatin (125μg/m²). Insulin binding to RBCs was measured by a modified method of Gambhir and was compared with SSPG.
Of 21 children with various relative body weight, 8 hyperinsulinemic obese children had a decreased insulin binding to RBCs due to decreased receptor concentrations.
The insulin binding was inversely correlated with the fasting serum insulin level and with the insulin area under the O-GTT insulin response curve. In 11 children with various relative body weight, a highly significant inverse relationship was found between SSPG and insulin binding. SSPG was also correlated with the fasting serum insulin level.
It was concluded that RBC insulin receptor may quantitatively reflect insulin resistance in obese children, and may be a useful tool for clinical evaluation of tissue insulin sensitivity in children.

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A 51-year-old woman with chronic lymphocytic thyroiditis showed transient thyrotoxicosis at seven weeks after cessation of steroid therapy for treatment of rheumatoid arthritis. Radioactive iodine uptake was only 3% even in a thyrotoxic state. Aspiration biopsy, performed just before the development of hypothyroidism, revealed histological features compatible with chronic lymphocytic thyroiditis. At two months after the onset of thyrotoxicosis, hypothyroidism developed, and she was kept in a euthyroid state by 1-thyroxine replacement therapy. Irreversible hypothyroidism was comfirmed by the recurrence of hypothyroidism after cessation of thyroid replacement therapy at one year after the onset of thyrotoxicosis. The causal relationship between the cessation of steroid therapy and the occurrence of transient thyrotoxicosis is discussed.

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To determine the effects of S-Adenosyl methionine (AdoMet) on TSH receptor function and adenylate cyclase coupling, human thyroidal crude membrane fraction was pretreated with AdoMet and with S-Adenosyl homocysteine (AdoHcy), separately or in combination. ¹²⁵I-TSH binding to the pretreated membrane and adenylate cvclase activity of the membrane were examined. In contrast to the reported effect of AdoMet on the decrease in GH binding to lactogenic receptor, AdoMet 0.5μ moles/ml significantly increased the binding of TSH to the receptor by increasing the affinity of the binding, whereas it decreased the coupling of adenylate cyclase significantly. The effect of AdoMet was partially counteracted by the pretreatment of the membrane with AdoHcy. This effect of AdoMet is very similar to that of diamide previously reported. The result implies that the effect is due to an alteration in the tertiary structure of receptor protein triggered by methylation.

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Previously we reported that the heart norepinephrine concentration was markedly increased in diabetic rats. To further study the relationship between a disturbance in the autonomic nervous system and catecholamine metabolism in diabetes mellitus, the plasma catecholamine response to stress and catecholamine concentration of heart and adrenals were measured. Wistar male rats were made diabetic by streptozotocin and kept for 13 weeks. A silicon catheter was placed in the superior V. cava 1 week prior to the experiment. Insulin was injected scbcutaneously for 3 days once daily. After an overnight fast and without anesthesia, 1 ml of blood, a control sample, was obtained and then the animals were exsanguinated. The blood was mixed with 1 mM EGTA at a final concentration and centrifuged. The tissue was homegenized with 0.4 N perchloric acid containing 1 mM EGTA and centrifuged at 10, 000×g for 20 minutes. Catecholamines were determined by high performance liquid chromatography. Normal rats responded to blood withdrawal stress, and plasma catecholamines were markedly increased, but almost no increase or an actual decrease was observed in diabetic rats. These abnormal responses were improved by insulin treatment.
Heart norepinephrine was increased significantly in the diabetic rats compared with the control rats and was reduced significantly by insulin injections. Adrenal epinephrine was also significantly increased in the diabetic rats compared with the control rats, but was not significantly reduced by insulin. These result suggest a possible disturbance of catecholamine secretion in the diabetic rats.

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[¹²⁵I] labelled [D-Leu₆, des-Gly-NH¹⁰₂] LH-RH ethylamide (LH-RHa), when injected into immature female rats, bound specifically not only to the pituitary but also to the ovaries. LH-RHa inhibited hCG-stimulated progesterone production and ovarian weight augumentation in hypophysectomized immature female rats in vivo. FSH-induced ovarian hCG receptors and ovarian weight gain in diethylstilbestrol (DES)-treated hypophysectomized immature female rats were also suppressed by LHRHa. Progesterone production by rat luteal cells in vitro was inhibited by LH-RHa. LH-RHa did not change the affinity or population of LH/hCG receptor in porcine granulosa cells in short term incubation. However, LH-RHa inhibited induction of LH/hCG receptor stimulated by FSH and insulin in long term culture of porcine granulosa cells. LH-RHa delayed hCG-stimulated cyclic AMP accumulation in porcine granulosa cells. These findings suggest that LH-RHa inhibits hCG-stimulated cyclic AMP accumulation and subsequent progesterone production as well as FSH-stimulated LH/hCG receptor induction by acting directly on ovarian cells.

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Serum thyroxine binding prealbumin (TBPA) levels in various thyroidal states were examined by radioimmunoassay (RIA). This technique is highly sensitive, accurate and reproducible. The normal mean (±2SD) level of serum TBPA is 26.9±8.0 mg/dl (29.4±5.2 in men and 24.9±7.6 mg/dl in women). Serum TBPA levels in pregnant women were significantly lower than in normal females (P<0.05). Serum TBPA levels in patients with untreated hyperthyroidism were 12.9±4.0 mg/dl (mean±SD) and in patients with untreated hypothyroidism were 25.2±4.7 mg/dl (mean±SD). The mean TBPA concentrations in untreated hyperthyroidism were significantly lower than that for normal population (P<0.01), but untreated hypothyroidism was almost within normal range. The changes in TBPA levels in hyperthyroidism and hypothyroidism were similar to those in TBG levels. In untreated hyper-and hypothyroidism, restoration to euthyroidism by treatment was uniformly accompanied by a normalization of serum TBPA and TBG levels.
A negative correlation between serum thyroid hormone binding protein (TBG and TBPA) and free thyroxine was observed in patients with hyperthyroidism. The coefficient of correlation between TBPA and free thyroxine was -0.80 (P<0.01) and between TBG and free thyroxine -0.58 (P<0.01).
From these experiments it appears that not only TBG but also TBPA may play an important role in the regulation of the free thyro xine concentration in response to various thyroidal states.

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Effects of MK 421, a new angiotensin-converting enzyme inhibitor, were studied normal men and patients. MK 421 was given at 0900 h as a single oral dose of 20 mg, to 5 normal men and 2 patients with essential hypertension and 10 mg to a patient with Bartter's syndrome, in the recumbent position. In all of them blood pressure (BP) fell, plasma angiotension I (P1 AI) and plasma renin activity (PRA) increased, and plasma aldosterone (PA) decreased from 2 h to 6 h. Maximum effects were observed at 4 or 6 h. Then the effects attenuated gradually but still remained 24 h. In the same 5 normal men angiotension I (AI) was infused iv at a rate of 20 ng/kg Emin from 0900 h to 1500 h, from 2030 h to 2100 h, and the next morning from 0830 h to 0900 h. At first the BP rose and PA increased. The onset of the BP fall was at 35, 55, 60, 70 and 85 min in each subject, respectively. Then the BP and PA began to decrease and the P1 AI and PRA began to increase. The maximum effects were observed at 4 or 6 h. Then these inhibitory effects on the AI were attenuated but still remained at 24 h. The 2 patients with essential hypertension and patient with malignant hypertension were treated with MK 421 at a daily doses of 5 to 40 mg for 2 to 6 months. They all showed a fall in BP and no side-effects were noted. From these results it is concluded that MK 421 is a strong and long-acting antihypertensive drug and its clinical application seems very useful for the treatment of hypertension.

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Insulin receptors on hepatocytes and erythrocytes were studied in rats two and eight weeks after the injection of streptozotocin (50 mg/kg) to see if erythrocyte insulin receptors change parallel with hepatocyte insulin receptors in response to hypoinsulinemia.
Insulin bindin to hepatocytes increased two (14.0±2.5% v.s. 7.7±0.7%; P<0.025) and eight weeks (15.9±1.9% v.s. 6.6±1.1%; P<0.005) after the streptozotocin injection. Scatchard analysis revealed that this increase was due to a rise in both the receptor concentration and affinity. The number of receptors was comparable in the two-and eight-week-streptozotocin rats while the increase in the affinity was more pronounced in the latter group. Insulin bindin to the erythrocytes was also increased in both two-(5.0±0.7% v.s. 4.2±0.6%) and eight-week-(4.3±0.6% v.s. 2.7±1.2%) streptozotocin rats. This increase was due to a rise in the receptor concentration rather than the affinity. However, compared to hepatocytes, these changes were inconsistent and statistically not significant. Furthermore, no correlation was obtained between the bindin and plasma insulin concentration.
These results indicate that insulin receptors on rat erythrocytes are less sensitive to a change in the plasma insulin concentration and do not always reflect accurately the receptor state on hepatocytes.

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The Relationship between ouabain-sensitive ATPase (Na-K ATPase) activity in erythrocytes and the thyroid status was studied in 36 patients with Graves' disease and 58 patients receiving L-thyroxine (T4) replacement therapy. Forty normal children served as control. Total ATPase activity in 4 untreated hypothyroid patients was significantly reluced (11.0±4.6 vs 17.3±4.1μg-P/h/mg-protein, P<0.01), and Na-K ATPase was undetectable, both of which were normalized after 4 weeks of L-T4 therapy. Na-K ATPase in hyperthyroid patients was also decreased (0.9±0.8 vs 4.0±2.7, P<0.01), but was gralually normalized after 3 months of euthyroil state.
Clinically euthyroid children treated with L-T4 were divided into 2 groups with regard to Na-K ATPase activity, normal and low. Analysis of the possible factors prolucing this difference revealel that, in primary hypothyroidism, the factor appeared to be the endogenous T4 level, while in patients with dwarfism, the secretory capacity of TSH or TSH-releasing hormone (TRH) was contributory. Thus Na-K ATPase activity in red cells remains within the normal range after L-T4 replacement in the presence of a severe degree of primary hypothyroidism or in association with secondary or tertiary hypothyroidism. Other factors such as the L-T4 dose, duration of the therapy, serum T4 and T3 concentrations, were not significantly different in the two groups. These results indicate that (1) Na-K ATPase in red cells is decreased in hyper-or hypothyroid state, (2) restoration of normal activity requires 1-3 months of euthyroid period, and (3) it is a sensitive index of peripheral thyroid status over the preceding few months.

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Three cortisol fractions, protein-unbound (U-F), transcortin-bound (Tr-F) and albumin-bound cortisol (Al-F) were measured in patients with dysproteinemia by a newly devised isocolloidosmolar equilibrium dialysis method. Total cortisol (Total-F) concentrations in patients with liver cirrhosis (LC), anorexia nervosa (AN) and cachexia due to cancer (CA) were higher than in normal subjects, and those in patients with nephrotic syndrome (NS) and multiple myeloma (MM) remained within the normal range. In all groups of patients, the U-F concentration, which is believed to be the sole active fraction of cortisol, showed significantly higher values than in the normal subjects. We, therefore attempted to find which of the two binding proteins contributes to the elevated U-F concentrations. Concentrations of each cortisol fraction are greatly changed by alterations in the Total-Fconcentration. We therefore compared the Tr-F against Total-F and Al-F, and U-F against Total-F of patients with those of normal subjects. It was found that decreasedtranscortinbinding and not albumin-binding in the patients with cirrhosis, nephrotic syndrome and myeloma contributed to an increase in the U-F concentration. Although decreased binding of albumin due to hypoalbuminemia was found in LC, NS, MM, CA and AN, it had relatively little effect on cortisol distribution inthe serum.

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Acute and intense hemorrhage in the anterior lobe of the pituitary was observed in mice treated with hypertonic solutions. The onset of hemorrhage and the spontaneous recovery phase were studied with light and electron microscopes.
Ten minutes after ip injection of 9% NaCl, 8% NaHCO3, 3 M glucose or 3 M sucrose at a dose of 0.03 ml/g B. W. there was selective bleeding in the anterior lobe of the pituitary. The maximum extent of hemorrhage was reached 12 h after the injection of hypertonic solution and lasted for approximately 3 days. Ontogenetic study indicated that no pituitary hemorrhage occurred in mice younger than 2 weeks of age.
Hypophyseal cleft was found to be not merely a residual lumen but an active site providing for accumulation and digestion of blood cells which flowed out of the bleeding anterior pituitary.
By the end of a week, the necrotic tissue in the center of the anterior pituitary was replaced by granulation tissue consisting of fibroblasts, macrophages, capillaries and a stack of exess basal lamina.

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Studies on the electrolyte metabolism and the renin-angiotensin-aldosterone system were made in a 47-year-old female patient with factitious Bartter's syndrome induced by surreptitious use of furosemide. The diagnosis was confirmed later by detection of the diuretic in the urine. In metabolic studies patient exhibited abnormalities similar to those reported in Bartter's syndrome; viz, hypokalemic alkalosis, blunted response to exogenous angiotensin II, which reverted to normal by volume expansion with an albumin solution, and diminished fractional free water clearance per fractional distal sodium delivery. The above data, along with the known pharmacological effects of furosemide, suggest that the abnormality in Na⁺ or Cl^- reabsorption in the ascending limb of Henle's loop is a primary cause of Bartter's syndrome.

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The effect of Amphenone B, an inhibitor of corticoid synthesis, on thyroxine (T4)-induced metamorphosis was studied in toad tadpoles kept in thiourea. Amphenone injections retarded T4-induced tail resorption markedly. The effect of Amphenone was nullified by aldosterone and corticosterone added to the water in which tadpoles were kept. Steroidogenic cells of adrenals in Amphenone-injected animals were enlarged markedly as compared with those in the saline-injected tadpoles or the Amphenone-injected tadpoles which were supplemented with corticoids. The results strongly suggest that endogenous corticoids act together with thyroid hormone to accelerate metamorphosis.

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