To clarify whether the reactivity of A cells is regulated by B cell function in the pancreas, plasma glucagon (IRG) responses to insulin-induced hypoglycemia and to arginine infusion were evaluated in streptozotocin (STZ; total 40 mg/kg) treated and control dogs. There was no significant rise in plasma IRG levels during the insulininduced hypoglycemia in the STZ-treated dogs. In contrast, arginine enhanced the IRG secretion from the pancreas to a similar extent in the two groups. This was deduced from the difference between IRG levels in the pancreaticoduodenal and peripheral veins. Neither intravenous glucose nor arginine infusion resulted in a significant rise in plasma insulin (IRI) levels in the STZ-treated dogs. IRI content in the pancreases of STZ-treated dogs was significantly reduced to 5 percent below the levels in the control dogs. The IRG content for control and STZ-treated dogs did not differ. These results indicate that while the responsiveness of A cells to hypoglycemia may depend on the secretory capacity of B cells, such is not the case with arginine.

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Transplantable human oat cell carcinoma cells of the lung with ectopic vasopressin production were incubated with labeled amino acids and immunoreactive neurophysins in cell extracts were analyzed by isoelectric focusing. When the cells were incubated with L-(₃₅S)-cysteine for 20 h, one major peak (isoelectric point; pI=5.3) and several minor peaks (pI=6.1, 5.7, 5.6, 5.1, 4.9 and 4.7) of labeled proteins were observed. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the relative molecular mass (Mr) of the pI 5.7 protein was estimated to be 20, 000 and that of the pI 6.1 species to be 19, 000, while the remainder had a Mr of approximately 10, 000. The result of the pulse-labeling experiment has clearly shown that the pI 5.7 and 6.1 proteins, which have affinity for concanavalin A, are biosynthetic precursors for the smaller form of neurophysin with a pI 5.3. When subjected to limited proteolysis with trypsin, the pI 5.7 protein generated a Mr 10, 000 protein and a smaller peptide. The Mr 10, 000 protein thus produced was identified as neurophysin on the basis of its pH-dependent affinity for vasopressin and the migration pattern on isoelectric focusing. The smaller peptide coeluted with synthetic arginine vasopressin and bound to neurophysin suggesting that it possesses a cysteine-tyrosyl sequence at its Nterminus. Similarly, the pI 6.1 protein liberated neurophysin and vasopressin-like peptide after incubation with trypsin. These results suggest that the glycosylated protein with a pI of 5.7 and a Mr of 20, 000 is the common precursor to vasopressin and neurophysin in human oat cell carcinoma of the lung with ectopic vasopressin production. The pI 6.1 protein may be an intermediate in the conversion of the precursor to vasopressin and neurophysin.

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The excised parathyroid glands of twenty-one patients with secondary hyperparathyroidism due to chronic renal failure were submitted to careful histopathologic examinations including electron-microscopy. The previous history of these patients who had been on hemodialysis treatment for a certain period was relatively uniform with no association with primary hyperparathyroidism.
Although eleven patients had four evenly enlarged parathyroid glands, eight patients showed four unevenly enlarged parathyroid glands with one or two glands weighing less than 100 mg.
Histopathologic patterns of hyperplasia are easily divided into two distinctly different patterns, diffuse and nodular. Thirteen cases showed the same histopathological patterns of hyperplasia, either diffuse or nodular, in all excised glands. However, one or two out of four glands in eight patients evidenced a different histopathological pattern.

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Antinuclear antibodies (ANA) were detected both in type 1 diabetic children and in control subjects. The incidence of ANA in eighty of these diabetics was 16.3%, as determined using two different substrates, human pancreas and human peripheral leucocytes. The incidence and the patterns in the detection of ANA were the same.
Four hundred and seventy-three children and one thousand one hundred and twenty-five adults served as the controls. The incidence of ANA in non-diabetic children was 0.8% and that in one adult population was 1.1%. Therefore, the incidence of ANA in childhood diabetics was significantly higher.
We studied autoantibodies in childhood diabetics, in normal children and in one adult population. Pancreatic islet cell antibodies (ICA) were detected in 29 out of 80 type 1 diabetics (36.3%) in two out of 473 normal children (0.4%) and in six cases in one population (0.5%). Thyroid microsomal antibodies (MCHA) were detected in 9 out of 80 childhood diabetics and the incidence of MCHA in type 1 diabetics was significantly higher than in the controls.

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Dynamics of the steroid recptors seems to be the consequence of receptor recycling. In the present study, as a clue to elucidate the mechanism of receptor recycling, factors which affect the rate of liberation of nuclear bound 3H-glucocorticoids were examined in vitro. Among the factors examined, NAD, NADPH, cAMP and pnitrophenyl phosphate accelerated the liberation of radioactivity from nuclei in a temperature-dependent manner when added to the incubation mixture. The presence of a large amount of unlabeled dexamethasone (Dex) did not modify the rate of liberation. From these results, it was concluded that the metabolism of ligand bound to the receptor is not a necessary step in the liberation of receptor from nuclei. These agents did not influence the binding process of 3H-Dex-receptor complex to DNA-cellulose. Therefore the stimulation of receptor release does not seem to be mediated by reducing the binding affinity between nuclei and receptor complexes. The liberated radioactivity was eluted on a Sephadex G-100 column in the void volume and in macromolecule-unbound fractions. In both fractions, the majority of the radioactivity comigrated with authentic glucocorticoids on thin-layer chromatography.

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This study was carried out to determine the effect of calcitonin on calcium and phosphorus absorption in sheep. Six sheep, which were prepared with a calotid loop and a portal venous catheter, were used. Thyroidectomized sheep were injected intramuscularly with porcine calcitonin at feeding time. Serum calcium concentrations did not change in intact or thyroidectomized sheep after feeding but calcium venoarterial blood differences in thyroidectomized sheep were higher than in intact sheep 8 h after feeding. Serum calcium concentrations and calcium veno-arterial blood differences were decreased by calcitonin injection into thyroidectomized sheep. Calcitonin injection also reduced the serum phosphorus concentrations. Phosphorus veno-arterial blood differences in thyroidectomized sheep were much less than in intact sheep before feeding although the blood differences were not affected by calcitonin injection in thyroidectomized sheep. The results indicated that calcitonin decreased calcium absorption, which caused a reduction in the serum calcium concentrations, and that calcitonin injection did not affect phosphorus absorption in thyroidectomized sheep.

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The T₃ suppression test by the 24-hr thyroidal ¹³¹I uptake was reevaluated in patients with Graves' desease before and after withdrawal of antithyroid drug. Fifty patients had been treated with propylthiouracil (PTU) or methylmercaptoimidazole (MMI) for 12 to 70 months. They were prescribed a maintenance dose of antithyroid drug (PTU, 50mg/day; MMI, 5mg/day) at the time of investigation and regarded as euthyroid on the basis of serum T₃, T₄ and TSH levels. Each patient was given 75mu;g T₃ daily for 8 days in conjunction with PTU or MMI. The 24-hr thyroidal ¹³¹I uptake was then measured (post T₃ uptake). In 30 patients whose post T₃ uptake was below 35%, treatment was stopped and the T₃ suppression test was repeated at one and 3 months later. During the two-year follow up, 24 remained well, while 6 relapsed within 4 to 12 months.
In patients with sustained remission, the post T₃ uptake was significantly lower in the MMI-treated group (13 cases, 7.7±1.0%) than in the PTU-treated group (11 cases, 18.6±1.9%). MMI withdrawal produced a marked rebound in the post T₃ uptake, whereas none of the patients showed the rebound after PTU withdrawal. In patients who relapsed later, there was no difference in the post T₃ uptake during treatment and the rebound occurred in the both groups following goitrogen withdrawal. Serum T₃, T₄ and TSH levels were within normal ranges at one and 3 months after cessation of antithyroid drug.
From the results of the present study, it is concluded that criteria for T₃ suppressibility by the 24-hr uptake should be determined by the antithyroid drug employed and by the time of investigation. There is a dissociation in the post T₃ uptake values following withdrawal of the two different antithyroid drugs.

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A male patient with recurring episodes of hypoglycemic attacks was diagnosed as having isolated ACTH deficiency as well as renal glycosuria and ichthyosis vulgaris. In addition, he had facial diplegia and abducens palsy consistent with Moebius syndrome, muscle atrophy with proximal dominancy, high arched palate, hammer toes, and mental retardation. There was electrophysiological evidence of peripheral neuropathy. Muscle biopsy of the deltoid showed mild myofiber atrophy with occasional cylindrical laminated bodies. The association of these disorders has never been reported and it could be coincidental. However, considering the high rate of association of isolated hypogonadotropic hypogonadism and Moebius syndrome with peripheral neuropathy, the present case may indicate a causal relationship between isolated ACTH deficiency and Moebius syndrome, reflecting the disorders in the organ systems derived from a common ectoderm.

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The effects of norepinephrine (NE) on the release of luteinizing hormone (LH) and LH-releasing hormone (LH-RH) were examined in a sequential double chamber perifusion system by perifusing the medio-basal hypothalamus (MBH) and/or pituitaries excised from normal female rats in diestrus. When the pituitary alone or in sequence with the MBH was perifused with medium containing 200μg/ml of NE, the concentration of LH in the efflux was significantly (p<0.05) increased to the level 50-150 % over the pre-injection control, whereas medium without NE had no effect. Perifusion of the pituitary in sequence with the MBH produced a higher peak level of LH than that attained by the perifusion of the pituitary alone. Administration of NE induced a significant increase in LH-RH release from the MBH, although the medium alone had no effect. These data suggest that NE induces LH release from the pituitary both by increasing LH-RH release from the MBH and by its direct action on the pituitary.

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Binding sites for ³H-dexamethasone (Dex) were demonstrated in cytosols from the ventral prostate and seminal vesicle of rats only if dithiothreitol (DTT) was present in the incubation mixture. The binding observed in the presence of DTT was high affinity (K_d=1-5 nM) and low capacity (B_max =approx. 0.1 p mole/mg protein) and exhibited a binding specificity for glucocorticoids. The addition of molybdate (Mo) to the incubation mixture enforced the effect of DTT on the binding but the exten of the effect of Mo in cytosols of the ventral prostate differed from that in the seminal vesicle. The binding sites in the cytosols of these tissues were depleted after administration of Dex to animals. The depletion observed was not due to occupation of the binding sites by injected Dex and this was confirmed by the exchange assay. Addition of the cytosol from the seminal vesicle inhibited the ³H-Dex binding in the liver cytosol but the cytosol from the ventral prostate did not show an inhibitory effect. The binding sites in neither of these male accessary sex organs were modified markedly after the animals were castrated.
Although the ³H-Dex binding sites observed in the cytoplasm of male accessary sex organs fit the definition proposed for the steroid hormone receptors, it is not clear whether these tissues are under the influence of glucocorticoid or not ; the rate of incorporation of ³H-leucine and ³H-orotic acid into the acid-insoluble fraction from the ventral prostate is not influenced by the administration of Dex to animals.

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Ten patients with idiopathic pituitary dwarfism were treated with methionyl human growth hormone (met-hGH) produced by recombinant DNA technology. They were given 0.5IU/kg/week of met-hGH for three months. There were no significant changes in physical, blood, urine examinations. Their height increased between 1.5 and 2.7 cm during the 3 months of treatment, which was calculated to be equivalent 6.0 and 10.8 cm per year with a mean increase of 8.7cm.
Anti-hGH antibody was observed in all patients between one and two months of treatment with a titer between 10¹×and 10⁴×. In spite of the formation of antibodies, the growth rate did not decrease in 7 of the 10 cases.

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The role of prolactin (PRL) and estrogen in the growth of 7, 12-dimethylbenz (a)-anthracene (DMBA)-induced rat mammary tumors was investigated. Tumor growth was suppressed by both bromocriptine and tamoxifen. Combined administration of ovine PRL and tamoxifen attenuated the inhibitory action of tamoxifen on tumor growth. Serum PRL levels were decreased by both bromocriptine and tamoxifen administration. Estrogen receptors (ER) in tumor tissues were decreased in number by tamoxifen, but not by bromocriptine. Progesterone receptors (PgR) in DMBAinduced mammary tumors were abolished by tamoxifen and significantly reduced by bromocriptine. Combined administration of ovine PRL with tamoxifen attenuated the inhibition of PgR induced by tamoxifen alone, while ER remained undetectable. Specific PRL binding to the liver was significantly reduced by treatment with bromocriptine, tamoxifen and tamoxifen plus ovine PRL, whereas PRL receptors in mammary tumor were not influenced by these drugs. These results suggest that PRL may stimulate DMBA-induced tumor growth independently of ER and that a part of the inhibiting effect of tamoxifen on tumor growth may be explained by the decreased PRL secretion.

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Tissue strip taken from rat uterine ampulla on day 20 of pregnancy was elongated at a constant rate in Tyrode's solution at 37°C to the length of a specified peak stress, and the stress decline was recorded at this length. The stress decline in uterine strips of ovariectomized progesterone-treated rats was significantly slower than those in intact pregnant rats at any different peak stress and elongation rate examined. Treatment with estradiol as well restored the physical properties to the control levels. Changing the medium to Ca-free Tyrode's solution had no effect on stress relaxation. Results suggest that estrogen with progesterone improves stress relaxation in the rat uterus during late pregnancy by changing the state of the noncontractile elements in the tissue.

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To investigate the mechanism of the central action of dopamine and its antagonist, metoclopramide, on the regulation of aldosterone, studies were performed in 54 conscious rats with and without bilateral nephrectomy. In normal and sham-operated rats, intracerebroventricular injection of dopamine resulted in a significant suppression of plasma renin activity and plasma aldosterone at 30min, and intracerebroventricular injection of metoclopramide resulted in a significant elevation of plasma renin activity and plasma aldosterone at 30 min without altering the plasma corticosterone and potassium levels. In bilaterally nephrectomized rats, the plasma renin activity was significantly reduced and it did not respond to dopamine or metoclopramide. In these rats, intracerebroventricular injection of metoclopramide exerted no effect on the plasma aldosterone, but intracerebroventricular injection of dopamine increased the plasma aldosterone slightly. However, this increase was not statistically significant.
These findings suggest that the dopaminergic system in the brain is involved in the regulation of aldosterone secretion, mainly with changes in the peripheral reninangiotensin axis in rats.

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Chicken LH components from the glycoprotein fraction of the anterior pituitary glands have been separated to isoelectric homogeneity by means of isoelectric focusing, and investigated for their biological activities in vitro. The activities of these components were measured with LH receptor binding, cyclic AMP accumulation and testosterone production in rat Leydig cells at equal doses expressed as immunoreactivity of IRC-2 (Gunma). All the components were active in the heterologous assay systems, although the relative potency expressed as the ratios of biological activity to immunoreactivity (B: I) differed significantly among the components. Component I, the amount of which is the largest (40-50%), with the most alkaline isoelectric point (pI) showed the highest B: I ratio, and the B: I ratio decreased with decreasing pI in the same way as in rat LH components (Wakabayashi, 1980; Hattori et al., 1983). Therefore, pituitary LH from photostimulated male quail, where the relative amount of component I was increased, was estimated to have higher B: I ratios than that from short-day (SD) treated male quail. Furthermore, the differences in activities among the components obtained by the three assays were in the following order: testosterone production>cyclic AMP accumulation>receptor binding, suggesting that the hormonal actions of components with higher B: I ratios (I, II and III) are efficiently amplified in the biological response to the final step. In the incubation of pituitary glands with hypothalamic extracts, component I in the pituitary glands from the long-day (LD) treated group was mostly decreased after the incubation, while all the components were decreased in parallel in the SD-treated group. The results suggest that the LH component releasable to GnRH changes in endocrine status though component I with the highest B: I ratio is relatively releasable in both SD-and LDtreated groups.

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The formation of glycosylated Hb by the nonenzymatic reaction between Hb and glucose suggests that glycosylation is a general reaction in the living body. We demonstrated by means of TLC and HPLC that T₃ was glycosylated when reacted with glucose in absolute ethanol for a week. We demonstrated in a metamorphic study in tadpoles that the biological activity of thus glycosylated T₃ was less than about 1/10 of that of T₃.
These findings suggest that glycosylation of substances with amino group other than serum proteins including Hb may occur and that glycosylated substances may differ in biological activities from the original substances.

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In order to investigate the antidiuretic hormone (ADH) in essential hypertensionand secondary hypertension, plasma ADH levels were measured in normal subjects, in patients with normal and low renin essential hypertension, and in other patients with various forms of secondary hypertension. Plasma ADH levels were significantly lower in low renin essential hypertension and higher in malignant hypertension than in normal subjects. The plasma ADH levels tended to be lower in renal hypertension and primary aldosteronism, and higher in renovascular hypertension, but these differences were not statistically significant. From these results, it appeared that ADH might play a role in malignant hypertension, but not in the other hypertensive diseases.

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Responses of plasma growth hormone (GH) and cortisol to insulin-induced hypoglycemia were repeatedly examined during a therapy of diabetes mellitus in a sub-totally pancreatectomized patient. During a mild control period of diabetes mellitus without any hypoglycemic attacks, insulin-induced hypoglycemia evoked a remarkable increase in plasma GH as well as cortisol while neither GH nor cortisol responded to insulin hypoglycemia during the strict control period with frequent episodes of hypoglycemia. On the other hand, plasma GH and cortisol responses to all other endocrinological stimuli were normal. The mechanism of such impaired hormone secretion during the strict control period of diabetes mellitus in this patient remains unclear.

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When whole plasma obtained from rats given carbon tetrachloride was applied to a column of Bio Gel P-30, P-150 or P-300, a large molecular form of immunoreactive glucagon (IRG), so called “big plasma glucagon” (BPG), was eluted in the void volume. Glucagon degrading activity, measured under the same conditions as for radioimmunoassay of IRG, was eluted in parallel with IRG. Since standard assay mixture containing aprotinin was used for the measurement of IRG, this degradation of glucagon might be due to an enzyme (s) other than serine proteinases. p-Hydroxymercuribenzoate depressed glucagon degradation and IRG in the BPG fractions to 20% and 30% of the control values, respectively. Other inhibitors of thiol proteinases, such as N-ethylmaleimide and leupeptin, also decreased the values for both glucagon degradation and IRG to a similar extent. However, phenylmethylsulfonyl fluoride and pepstatin had little or no effect on these values. On filtration of plasma from carbon tetrachloride-treated rats on a column of Bio Gel A-1.5 m, IRG peaks between 600 k and 1, 200 k daltons were obtained and glucagon degrading activity was again eluted with IRG. When p-chloromercuriphenyl sulfonate and N-ethylmaleimide were added to the elution buffer and assay mixtures, the glucagon degrading activity was almost completely inhibited and the values for IRG between 600 k and 1, 200 k daltons were decreased to less than 10% of those of the control. These results indicate that more than 90% of the IRG in the fractions of BPG obtained from carbon tetrachloride-treated rats could be accounted for entirely by the degradation of immunoreactive ¹²⁵I-glucagon by plasma proteinases, probably thiol proteinases. Thus we conclude that some proteinases are still active in the radioimmunoassay system of glucagon which is widely used at present, and lead apparently higher glucagon values owing to degradation of ¹²⁵I-glucagon.

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