The daily administration of β-estradiol benzoate (50μg or I mg) to hypophysectomized female rats for five consecutive days did not markedly alter ¹³¹I uptake by the thyroid gland. Estrogen or PMS increased thyroid uptake of ¹³¹I in TSH treated hypophysectomized rats. Similar results were obtained with estrogen but not PMS in hypophysectomized and oophorectomized animals. These observations show that estrogen can potentiate the TSH induced uptake of ¹³¹I by an extrapituitary mechanism.

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Various doses of parathormone were injected into rats, and calcium, inorganic phosphorus, alkaline phosphatase, α-L-glutamyl-β-naphthylamide splitting enzyme, L-leucyl-β-naphthylamide splitting enzyme, and L-leucinamide splitting enzyme were measured in serum simultaneously. Changes in these factors were dependent on the dose of parathormone.
Calcium concentration and α-L-glutamyl-β-naphthylamide splitting enzyme activity showed similar changes. Calcium concentration was increased by an injection of 300 U. S. P. parathyroid units/100g body weight, and was returned to the normal value by 600 units.α-L-Glutamyl-β-naphthylamide splitting enzyme activity was increased by 300 units of parathormone, then maintained a value slightly lower than normal by a dose from 450 to 1200 units.
Changes in the activities of L-leucyl-β-naphthylamide and L-leucinamide splitting enzyme were different. L-Leucyl-β-naphthylamide splitting enzyme activity was decreased by a dose from 300 to 900 units, and was returned to nearly the normal value by 1200 units. L-Leucinamide splitting enzyme activity was increased by a dose below 450 units, but was decreased to about half of the normal value by 1200 units. This indicates that L-leucyl-β-naphthylamide splitting enzyme is different from L-leucinamide splitting enzyme.
Serum alkaline phosphatase activity was decreased by a dose below 450 units and was maintained at 34% of the normal value by doses up to 1200 units.

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The degraded products of saliva-parotin-A (SPA) by Pronase P were investigated chemically and biologically. They were separated into 6 fractions by paper chromatography and the Rf value, recovery, chemical properties, and solubility of each fraction were determined. The maximum ultraviolet absorption was found at a wave length of 271mμ for Fraction 1, and 279mμ for SPA. The molecular weight of Fraction 1, which was the most active fragment, was estimated to be 400-500 by gel filtration through Sephadex G-25.

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The effects of glycyrrhizin on the pituithry adrenal axis were studied. Isolated rat anterior pituitary glands were incubated with ¹⁴C-phenylalanine and biosynthetic activity of corticotropin in the pituitary was estimated. The rate of incorporation of radioactivity from ¹⁴C-phenylalanine into corticotropin fraction in the rat anterior pituitary was increased specifically by prior adrenalectomy. Cortisone treatment suppressed the increased ¹⁴C-incorporation into the corticotropin fraction induced by prior adrenalectomy. However concomitant injections of glycyrrhizin blocked the inhibitory action of cortisone on ¹⁴C-incorporation into the corticotropin fraction. Glycyrrhizin was also found to be antagonistic to the suppressive action of cortisone on compensatory adrenal hypertrophy in rats after unilateral adrenalectomy. Under condition of stress, glycyrrhizin was found to increase the inhibitory action of cortisone on adrenal ascorbic acid depletion. The possibility of distinguishing the secretory mechanism of corticotropin in the basal stage from that in the condition of stress and the mechanism of the inhibition of glycyrrhizin on the action of cortisone are discussed.

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The effect of dexamethasone on pituitary-adrenal function was studied in rats for the purpose of developing a new assay method for corticotrophin-releasing factor (CRF) in vivo. Intraperitoneal administration of 0.2mg of dexamethasone and 5.0mg of Nembutal per 100g body weight lowered the plasma corticosterone concentration in saline injected rats (3.5±0.3μg) and suppressed the effect of a wide variety of stressful stimuli under the level of 10.0μg/100ml of plasma. This treatment also inhibited the corticotrophic activity of vasopressin in doses less than 80 mU of activity. Partially purified CRF from the posterior pituitary was tested at several dose levels; a linear dose response curve was obtained between 0.04 to 2.2μg of CRF and plasma corticosterone level.
It is proposed that the dexamethasone and Nembutal treatment is a new assay system for CRF, which is simple and suitable for routine assay procedure.
The relationship between CRF and vasopressin and the blocking mechanism of dexamethasone are briefly discussed.

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For the investigation of corticotrophin-releasing factor (CRF), it is necessary to prepare pure CRF, especially in a vasopressin-free form, since vasopressin itself can release ACTH in vivo and in vitro. Attempts were made to purify vasopressinfree CRF from the posterior pituitary powder of hog origin in the present study.
The acetone-ether precipitate of posterior pituitary powder was subjected to CMC column chromatography and CRF-vasopressin mixture was obtained. This crude material was purified by partition chromatography on Sephadex G-25 and separation of CRF from vasopressin was satisfactorily achieved. This purified CRF (PB-III) which was still contaminated with 15 IU/mg of vasopressin was active in ACTH release at a dose of 0.04μg in dexamethasone-Nembutal treated rats and yielded a single spot on a paper chromatogram.
For further purification, gel filtration on Sephadex G-25 was carried out on the purified CRF. Very highly purified CRF could be obtained with 7.5IU/mg of pressor contamination; this was active in ACTH release between 0.01 and 0.08μg per rat with a linear dose response. This is the highest purification of CRF ever reported.
Specific activity of CRF and contamination of vasopressin were listed on several CRF preparations obtained at various stages of purification and the methods of purification of CRF from vasopressin were discussed.

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Light and electron microscopic observations were made on the cells of the adrenal cortex of male immature and adult Syrian hamsters (Cricetus auratus) with or without unilateral adrenalectomy. In hamsters, the zona glomerulosa occupied the entire thickness of the cortex in November, while it was sometimes atrophic due to the invasion of the zona fasciculata in June. The glomerulosa cells contain mitochondria with cristae. The agranular endoplasmic reticula (ER) form a network spreading among the mitochondria. Groups of Golgi lamellae are scattered in the cytoplasm, sometimes forming a Golgi-ring. There are only a few fat droplets in glomerulosa cells. In the fasciculata cell, deformation of mitochondria was observed, and they had tubular projections instead of cristae. Elongation and multilamination took place, and eventually the mitochondria turned into lamellated membranes. Abundant vesicles may be identical with the cross-sections of dilated ER and Golgi lamellae are dispersed. One day after unilateral adrenalectomy, the zona glomerulosa was reduced in width. In these animals Golgi lamellae and vacuoles in the glomerulosa cells were quite frequently found, and mitochondria extensively elongated in normal fasciculata cells were simplified in shape, and turned into the usual ones with cristae. Vesicles in the fasciculata cells decreased in number. Within 7 to 10 days, however, cells of the zona fasciculata became under the normal state. Therefore, the response of fasciculate cells to unilateral adrenalectomy was not persistent in hamsters. In the present observation a role of Golgi apparatus in steroid hormone production was suggested, and further it was assumed that the network of smooth ER might be vehicles of precursor of steroid hormone.

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The gross chromosomal observations of Wistar-rat bone marrow cells during variable period of severe alloxan diabetes [11 to 12 days (group A), 19 to 22 days (group B), 31 to 44 days (group C), and 93 to 101 days (group D); and over 31 days, followed by 4 to 6 days insulin treatmcnt] as well as in control rats were performed in the shortest culture to find some of the effects of diabetic environment on the somatic chromosomes.
The following results were obtained:
1) The normal somatic chromosomes occupy 42 in number with very rare appearance of hypomodal cell (41) and each chromosome can be classified into 3 main components, J, V and Rod (R) shape, with two subgroups (R₁ and R₂) in the R type. The X chromosome belongs to the R₂ subgroup and the Y chromosome to the V group in the present investigation.
2) Minor chromosomal alterations have been observed in the diabetic groups of C and D, such as some hypermodal cells (43 to 45), fragmentations, additional minute chromosomes and thread-like configurations of short arm. The latter chromosomal aberration is a peculiar anomaly and needs further investigation to clarify the significance. Other chromosomal changes are not considered to be specific for alloxan diabetic rats.
3) The insulin treatment in diabetic rats of over one-month's (56 to 95 days) duration caused a normalization of their idiograms, showing a disappearance of hyperdiploid cells and gross anomalies in chromosomes.
The above facts are likely to indicate that a diabetic environment has an influence upon the somatic chromosomes of rats, as well as give evidence of mechanisms of transmission of diabetic traits.

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Three submicroscopic procedures for zinc-detection in β cells of the islets of Langerhans of adult pigs, rabbits and rats, were studied. In Procedure A (intra venous method with dithizone), portions of the pancreas were fixed in cold phosphatebuffered formaldehyde after an intravenous administration with dithizone and frozen sections of 40μ thickness were made. They were immersed in cold 1% silver nitrate solution with 5.7% sucrose for approximately 2 hours in a dark place. After washing, the tissues were cut into smaller pieces containing an islet using a stereomicroscope, followed by dehydration and embeddment into epoxy resin for electron microscopy. In Procedure B (modified Voigt's silver sulfide method) tiny pancreatic blocks were fixed in cold H₂S-saturated 70% alcohol in a dark place for approximately 2 hours. They were dehydrated and embedded in epoxy resin. Ultrathin sections were treated with the reducting agents containing silver nitrate, and observed under an electron microscope. Procedure C (paraffin-embedding method) was performed as follows: pancreatic tissue portions were fixed in absolute alcohol, embedded in paraffin and cut at 40μ. The sections, stained with dithizone, were immersed into 1% silver nitrate solution and developed with the reducing agent. They were then dehydrated and embedded in epoxy resin.
The above procedures for detection of zinc in β cells were easily reproducible except in Procedure C, in which considerable amounts of reduced silver grains were extracted during dehydration. Procedure B is an application of Voigt's silver-sulfide method for light microscopy but proved disadvantageous in that the intracellular structures of β cells were markedly disintegrated. On the other hand, Procedure A showed the sites of zinc and the preservation of β cell ultrastructure most satisfactorily in the earliest period after dithizone injection.
The reaction products, which correspond to the submicroscopic localizing sites of zinc, were demonstrated mainly in mature granules and on their encasing membranous sacs. A small amount were also present occasionally in relation to the endoplasmic reticulum.

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Many clinical and experimental data suggest that suckling can modify reproductive function. Among these are lactation amenorrhea, lactation diestrum and inhibition of castration changes in the anterior pituitary glands in puerperal rats. In the present work, FSH and LH content of the anterior pituitary glands in suckling and non-suckling rats following gonadectomy were assayed by means of the modified HCG-augmentation method of Steelman-Pohley and the modified OAAD method of Parlow, respectively. The results were as follows:(1) On Day 3 postpartum, all the mothers were gonadectomized and divided into the suckling and non-suckling groups. On Day 17 postpartum, they were sacrificed and pituitary FSH and LH content were bioassayed. The litters had a normal increase in body weight during the experimental period after the mothers were gonadectomized.(2) Both pituitary FSH and LH content in the castrated non-suckling group were approximately as high as the levels found in the simple castrated adult female rat. Those in the castrated suckling group were lowered to levels approximately equal to those in the intact suckling rats. The gonadotrophins of the suckling groups were significantly different from those in the non-suckling groups. Histological findings of the anterior pituitary glands were in agreement with the functional changes observed The present data confirm that suckling plays an important inhibitory role in pituitary gonadotrophin (FSH and LH) secretion in castrated puerperal rats. More physiological and useful therapeutic methods for the study of some reproductive disfunctions might be found through investigation of this mechanism, probably involving hypothalamico-hypophysial process.

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A puberal change in the secretory pattern of androgen was investigated in the rat. Using immature and adult rats which received an acute human chorionic gonadotrophin (HCG) stimulation, androstenedione and testosterone were measured both in the testicular venous blood (TVB) and in the testis by means of gaschromatography after preliminary separation by paperchromatography. In contrast to the adult pattern of testosterone-dominance, an androstenedione-dominant pattern was found in the immature rat. The change from immature to the adult pattern was assumed to take place at around day 40, being coincident with the onset of puberty in this species. The adult pattern of androgen secretion, however, could not be induced precociously even in the immature rat pretreated with HCG for 2 weeks, up to 34 days of age.
The ratio of testosterone to androstenedione in TVB or in the testis of the intact adult animal was significantly increased by an acute stimulation of HCG. This finding is discussed in connection with the locus (ci) in the pathway of testo-sterone-biogenesis which HCG accelerates.

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Calcium disodium ethylendiaminetetracetate (Ca-Na₂-EDTA) 70mg/kg body weight dissolved in 300ml of 5% glucose was infused in 17 normal subjects, 11 cases of postoperative hypoparathyroidism, 2 cases of idiopathic hypopararhyroidism, and 4 cases of latent hypoparathyroidism, to evaluate the recovery from hypocalcemia. Serum calcium was determined before, immediately after, and 1, 2 and 3 hrs. after the end of the infusion to calculate the Approximate Expected Time of Recovery from the amount of serum calcium decrease and the recovery at the end of 3hrs. A markedly delayed recovery from hypocalcemia characterized all forms of hypoparathy roidism. Infusion of 400 units of parathyroid extract immediately before the test restored the recovery towards normal in these cases. Ca-Na₂-EDTA appears to be less toxic than Na₂-and Na₃-EDTA and no side actions related to hypocalcemia were seen in any case, in spite of the rapid infusion over a period of 20 minutes as compared with 2hrs. required when Na₂ or Na₃-EDTA was used. The recovery of serum calcium was also faster following infusion of Ca-Na₂-EDTA than after administration of similar amounts of Na₂ or Na₃-EDTA.

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