The effect of morphine on adrenal-pituitary axis function was examined by determination of adrenal and serum corticosterone changes in rats pretreated with dexamethasoe.
Increases in both adrenal and serum corticosterone concentrations induced by a single dose of 20mg/Kg of morphine were almost completely inhibited by subcutaneous injection with 1mg/rat of dexamethasone 3 hr prior to morphine administration. However, no suppressive effect of dexamethasone was observed when a dose of 30μg/rat of synthetic ACTH was given.
In morphinized rats, adrenal and serum corticosterone concentrations were not so significantly increased as observed in a single dose of morphine administration. However, corticosterone concentrations after the morphinization were increased strikingly by synthetic ACTH or nalorphine administration immediately after the final treatment of morphine. But these increases after nalorphine administration were inhibited entirely by the pretreatment with dexamethasone.
On the bases of these findings, it was suggested that morphine dose not act directly corticoidogenesis in adrenal cortex but affects through the central nervous system.

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A new method for the measurement of triiodothyronine (T₃) in sera was described. All through the assay, a small column of Sephadex G25 suspended in 0.1N NaOH was employed. After the preparation of the column in 2.5ml syringe, 250μl 0.1N NaOH solution containing ¹²⁵I-T₃, 100μl standard solution and 100μl T₃-free serum or sample serum were added and passed through the column. After washing out with 2.0ml of 0.063 M phosphate buffer pH7.4, 0.4ml diluted antiserum (1: 300) was added. The column was counted by a well counter (the first count). After 1hr incubation, the column was washed again with 1.5ml phosphate buffer. The second count of the column representing unbound T₃ radioactivity was performed. Percent retention was calculated from the ratio of the second to the first count. Percent retention was shown to relate to the dose of T₃ in the range from 31.3 to 1, 000pg/100μl.
The concentration of T₃ in sera of 12 normal, 4 TBG-deficient, 9 hypothyroid, and 13 hyperthyroid subjects was 148.3±24.4, 52.5±20.7, 53.3±27.2 and 425.4±110.8 ng/100ml (mean±SD), respectively.

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Intravenous administration of 0.4g/kg D-glucuronolactone or L-gulonolactone, the precursors of xylitol in the glucuronate-xylulose cycle, produced only small increases in plasma insulin in dogs. The plasma insulin responses were far less than those following the equivalent dose of xylitol, and are presumably explained by the concomitant small rises in plasma glucose. Infusions of ribitol, L-arabitol or D-arabitol (2mg/kg. min) into the pancreatic artery of dogs did not produce any significant increases in plasma insulin concentration in the pancreatic vein, while xylitol and glucose infused in a similar manner always stimulated insulin release. These data appear against the direct involvement of the glucuronate-xylulose cycle or the pentose phosphate pathway in the mechanism of insulin secretion. The mechanism of strong insulin-releasing effect of xylitol in dogs remains unexplained.

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Glucose was administered to a fresh water teleost, Channa punctatus. Three groups of 40 fish each were injected intramuscularly with 1/2, 1 and 2 g/kg body weight glucose. Blood glucose level of the experimental fish was assayed according to Nelson (1944) at predetermined intervals, ranging from 0 to 120 hr post-injection. The principal islets were removed at autopsy and fixed for histological examination. A group of 20 fish injected with plain distilled water served as controls.
A dose dependent hyperglycemic response was obtained after the glucose loading in Channa punctatus. The peak values were recorded within one hr of the injection. The beta cells in the principal islets were degranulated as a consequence of the glucose injection. The degenerative changes in the beta cells, which included loss of specific granules, pycnosis of nuclei and vacuolization, occurred in synchrony with the fluctuations in the glycemic level. The histological changes in the beta cells were interpreted to be resulting from an increased demand for insulin to metabolize the excess glucose, thereby indicating the role of these cells in the blood glucose homeostasis in this fish.

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The activity of pyridine nucleotide-linked 17β-and 20α-hydroxysteroid dehydrogenase (s) was detected in HeLa S₃ cells. Addition of progesterone to cultures failed to increase the 20α-hydroxysteroid dehydrogenase activity of the cells. The enzyme was partially purified by ammonium sulfate fractionation and chromatography on Bio-gel P-100, and the molecular weight of the enzyme was estimated at approximately 30, 000. The enzyme (s) could operate progesterone, 17α-hydroxyprogesterone (20α-hydroxysteroid dehydrogenase) and androst-4-ene-3, 17-dione (17β-hydroxysteroid dehydrogenase) in the presence of either NADH or NADPH. However, there was a small difference of elution patterns from the Bio-gel column between the NADH-and NADPHlinked enzymes, while the NADPH-linked 17β-hydroxysteroid dehydrogenase activity was eluted at the same void volume as the NADPH-linked 20α-hydroxysteroid dehydrogenase activity.

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This work aims to clarify whether the pars distalis of the pituitary gland plays an indispensable role in heat-induced sex transformation from ovaries to testes. Intact and hypophysectomized tadpoles of the sex semidifferentiated race of Rana catesbeiana were reared in water at 20°C as controls and at 30°C as experimentals. The results showed that ovaries of the hypophysectomized tadpoles were sex transformed to testes completely or partially both at 20°C and 30°C, demonstrating independence of spontaneous and heatinduced sex transformation on the pars distalis. The findings were in agreement with our previous work that sex transformation of ovaries was independent of thyroid function, and also with reports from other laboratories that sex transformation induced with sex hormones likewise occurred in hypophysectomized as well as in intact tadpoles. Therefore, it is believed that the pars distalis is not essential for sex transformation and that heat delivers, without mediation through endocrine glands, a direct and destructive assault on the cortex of the gonad which elicits the antagonistic activity of the medulla, resulting in sex transformation.

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By using the double isotope derivative dilution method, in which the carbonyl group at C-3 alone is derived to thiosemicarbazone-³⁵S as reported previously, microdetermination of cortisol, corticosterone, cortisone, aldosterone, deoxycorticosterone, and progesterone in erythrocytes, granulocytes, lymphocytes, and platelets of human adult male blood was carried out. The relationship between the quantity of these corticosteroids added and their incorporation into these cell fractions, and the saturation volume of incorporation and the relationship between saturation volume and steroid structure were examined.
In normal human blood, corticosteroids amounting to 38.46-58.85% of the total quantity are present in plasma, those amounting to 26.10-36.55% in erythrocytes, 3.02-8.55% in granulocytes, 2.50-4.27% in lymphocytes, 0.72-2.30% in platelets, and 8.74-11.58% in other fractions. The quantity of corticosteroids calculated as the amount per cell in granulocytes and lymphocytes was about 150-300 times larger than that in erythrocytes, and 0.7-1.6 times lager than that of erythrocytes even in platelets.
Incorporation of corticosteroids into blood cell fractions in vitro differed markedly with the kind of steroids and cell. The saturation volume in blood cell fractions was about 3-10 times larger in steroids with small polarity than in those with large polarity. This fact proves that the saturation volume of incorporation of corticosteroids in blood cell fractions is correlated the polarity of steroids. Furthermore, the saturation volume calculated per cell in granulocyte, lymphocyte, and platelet was about 25-130, 16-50, and 1-4 times that in erythrocyte, respectively.

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Calcium absorption from rat duodenal loop was measured in vivo by placing 0.2 mg Ca as CaCl₂ solution with or without ⁴⁷Ca into the loop, followed by measurement of the decrease of Ca and/or ⁴⁷Ca in the loop. Synthetic tetragastrin, 10-40μg/kg body weight, administered subcutaneously immediately before placing Ca solution in the loop, stimulated calcium absorption from the loop in intact rats, but not in animals parathyroidectomized or thyroparathyroidectomized 24hr prior to the experiment. Stimulating effect of tetragastrin on calcium absorption from the intestinal loop thus appears to require intact parathyroid. Acidification of the loop content failed to influence the calcium absorption from the loop, so that the effect of tetragastrin is probably not mediated by acid secretion. Since gastrin is secreted in response to calcium load and calcitonin release is stimulated by gastrin, these two hormones appear to form a functional unit to maintain calcium homeostasis, especially on the basis of this new property of gastrin increasing calcium absorption.

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Human growth hormone (HGH) secretion occurred following the administration of Gly¹-ACTH (1-18) octadecapeptide amide (50022-S) which was synthetized by Otsuka.
The mean response curve of plasma HGH after the intravenous administration of 0.35mg of 50022-S in 23 healthy subjects was similar to that of plasma cortisol.
A significant increase in plasma HGH to 0.35mg of 50022-S was observed, while there was no significant increase in plasma HGH to 0.25 mg of 1-24 ACTH, which is a corresponding dose to 0.35mg of 50022-S in cortisol response.
In most of the patients who had dysfunction of hypothalamic-pituitary axis, no significant increase in plasma HGH to 0.35mg of 50022-S was observed.
From these results, we conclude that Gly¹-ACTH (1-18) octadecapeptide amide (50022-S) has a potency to release growth hormone from the pituitary in man.

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The metabolic patterns of HCG in response to 5% glucose, arginine-saline and arginine-glucose infusion were investigated in normal postpartum women. Serum HCG concentration was measured by a double antibody radioimmunoassay method.Following arginine-glucose infusion, serum HCG level declined significantly within 30min of the infusion, while 5% glucose or arginine-saline infusion failed to produce any change in HCG concentration. Changes of blood glucose concentration during arginine-glucose infusion was similar to that during 5% glucose infusion. The possible reasons for the decline of serum HCG level after arginine-glucose infusion are discussed in this paper.

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To elucidate the role of cAMP-dependent protein kinase in steroidogenic action of ACTH, effect of ACTH administration on the rate of protein phosphorylation in the adrenal subcellular fractions were examined by injecting ³²P-orthophosphate to rats 30 min before the death of animals. Bulk of the radioactivity was observed in the alkali-labile phosphorous from the nuclear fraction. Administration of ACTH caused a significant elevation in the radioactivity of the microsomal protein when compared on weight basis protein but the radioactivity in the other three fractions was not changed by the same treatment of animals. These results appeard to provide another evidence for that the site ACTH action mediated by cAMP is localized in microsomal fraction of rat adrenals.

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One mg of testosterone propionate in olive oil was injected subcutaneously to female rats on the 5th day after birth. The animals which showed persistent vaginal cornification were thyroidectomized at the age of 10 to 12 weeks. Leukocytic and epithelial vaginal smears appeared within 1 to 2 days after the operation. Irregular cyclicity with the pattern of 2 to 6 days vaginal diestrus and 3 to 10 days estrus continued for as long as a month. Histological examination confirmed the corpora lutea formation in the ovaries of androgen-sterilized+thyroidectomized rats, but did the exclusive existence of vesicular follicles in the ovaries of the androgen-sterilized controls. These results suggest a rapid enhancement in the LH release in androgen-sterilized rats following thyroidectomy.

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A 5α-dihydrotestosterone binding component, sedimenting with a sedimentation constant of 8.6S, was detected in rat hypothalamic cytosol labelled in vitro with 5α-dihydrotestosterone-3H. The dissociation constant of the androgen-protein complex and the number of binding sites of the component were approximately 7.4×10^-10M and 0.9×10^-14 moles/mg cytosol protein, respectively. The binding component seemed to have a specificity for 5α-dihydrotestosterone relative to other hormones. These results suggest that the cytosol from male rat hypothalamus contains “receptor” for 5α-dihydrotestosterone.

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