1) 6-Ketoprogesterone (6 kp) can not demonstrate the progestin effects by Hooker-Forbes' method.
2) 6Kp has little androgenic and estrogenic action.
3) 6Kp has myotrophic (anabolic) action almost as strong as progesterone.
4) 6Kp has the hypertrophic action on the preputial gland which is almost equivalent to that of 17 (α)-hydroxyprogesterone, 17 (α)-methyl-Δ⁵-androstene-3 (β)-17 (β)-diol.
5) 6Kp (large dose), has depressant effect on the central nervous system, resembling progesterone in variation with sex and lack of excitation at the induction of anesthesia, displays one-sixth to one-seventh of its potency.
6) The spinal reflex is accelerated by 6kp similar to progesterone.
7) 6kp has little influence on blood pressure.
8) The steroid, which is produced in the placenta and which has myotrophic, anabolic action and hypertrophic effect on the preputial gland without androgenic action, is possibly 6kp or its related compound.
9) The vaginal smear cycle in the rat is under the control of estrogen and progesterone.

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The larvae of Rhacophorus schlegelii were treated with 0.033% thiourea solution, 0.033% thiourea+0.005% PHP solution, or 0.005% PHP solution, and the infl uences of these treatments on the hypophyses, thyroid glands and gonads were observed.From these results it is emphatically suggested that the levels of secretion of anterior-hypophyseal hormones are influenced by PHP treatment, and consequently the oversecretion of thyroid stimulating hormone does not occur in spite of thiourea treatment, and not only the degree but the direction of the gonadal differentiation may be influenced by the unusual secretion of anterior-hypophyseal hormones.

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1. The tadpoles of Rhacophorus schlegelii were treated with methylmercaptoimidazole, and the effects of this substance on the thyroid gland and the gonad were studied.
2. The metamorphosis-inhibiting effect of this substance is about ten times or more as strong as that of thiourea.
3. The influence of this substance on the thyroid gland and the gonad is essentially the same as that of thiourea treatment.
4. The acceleration of gonadal development and the sex reversal of female to male in higher anuran larvae induced by the treatment with thiourea are the common phenomena induced by any antithyroidal thiourea derivatives.
5. It is interesting that the direction of sex differentiation of larval gonad is easily affected by the unusual changes of levels of hypophyseal hormones.

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Glutamic dehydrogenase and glutamic-oxalacetic transaminase were assayed of rat and dog tissues, such as thyroid, adrenal cortex and medulla, anterior and posterior pituitary, liver, kidney, heart and cerebral cortex.It was observed that activity of these enzymes was generally lower in endocrine tissues than in nonendocrine ones.Enzymic activity of the thyroid was the lowest among all the tissues examined.Liver and kidney were found highly active.Interrelationships between these findings and the physiological functions of some of these tissues were discussed with special reference to thyroid physiology.

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A definite daily dose of calcium mesoxalate was orally given to rats, and to young and adult dogs, for long periods and change in pancreatic insulin content was investigated.
1. When 100mg/kg of calcium mesoxalate was daily given to rats for 1, 3, and 6 months, pancreatic insulin content was increased, most prominently in the 3 months group, becoming 1.5 times that of the control.
2. When daily doses of 10mg/kg and 50mg/kg of calcium mesoxalate were given to young dogs for 2 months pancreatic insulin content was increased to 2 times the control level, without any difference by sex.
3. When daily doses of 50mg/kg and 200mg/kg of calcium mesoxalate were given to adult dogs for 1 and 2 months, pancreatic insulin content was increased in the groups of the both doses for 1 month, especially prominently in the group of 200mg/kg for 1 month, attaining 2.5 times the control level. However, there was no difference from the control in the group of 50mg/kg for 2 months.

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Electrical stimulation was applied to the various sites of hypothalamus and the relationship between the points stimulated and the ovarian changes produced by the hypothalamic stimulation were studied, and the following results were obtained:
(1) The points (11 points) of which stimulation resulted in ruptured follicles were located in the posterior-ventral portion including the mammillary body, and some of them were located in the a'-area (ventrocaudal part of the arcuate nucleus and its vicinity) or in the periventricular layer of the hypothalamus. Stimulation of the lateral hypothalamic area in one case also induced ruptured follicles.
(2) The points of stimulation which produced hemorrhagic follicles (8 points) widely scattered throughout the medial portion of the hypothalamus.
(3) The ovulation produced by the hypothalamic stimulation was prevented by transection of the spinal cord in most of the cases, however, ovulation was elicited in these cases with negative ovulatory response by injection of pregnant woman urine. In 3 cases which received spinal cord transection at levels below twelfth thoracic segment, hemorrhagic follicles were induced by stimulation. It may be considered that the failure of the ovulatory response by spinal cord transection is attributable to the disturbance of ovarian circulation which transports the gonadtrophin released from the adenohypophysis by the stimulation to the ovaries.
(4) Ovulation (bleeding or luteinizing) was not induced by hypothalamic stimulation in ovaries transplanted in the anterior eye chamber, while it was produced by injection of a large amount of pregnant woman urine.
(5) Hypothalamic stimulation of one of a pair of rabbits, in which a cross circulation between jugular veins of two rabbits was made resulted in ovulatory response in both animals.
(6) The results may indicate that the area chiefly participating in the ovulatory function in rabbits is located in rather well defined area of the hypothalamus, mainly in the posterior-ventral part, and that the gonadotrophin released from the adenohypophysis by hypothalamic stimulation acts on the ovary and results in the ovulation.

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The effect of small repeated intravenous administrations of alloxan (1-20mg per kg per day) on glucose tolerance was examined in 20 rabbits.
The intravenous glucose tolerance curves from 6 rabbits intravenously given 1mg per kg per day of alloxan for 5 or 10 days, were steeper than those from controls. And those from 3 rabbits treated daily with 10-20mg per kg of alloxan for 10 days or more showed lower slope, resembling the diabetic one. These tendencies were neither transitory nor progressive.
Mechanism of action of alloxan was discussed briefly. It was concluded that 1mg per kg per day doses of alloxan given intravenously, stimulated the function of beta cells and 10 nag per kg per day doses or more produced a damage to beta cells in pancreatic islets of rabbits.

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Effect of ligation of several blood vessels on the degradation and distribution of I¹³¹-labeled Parotin in rat was studied. The degradation of the labeled Parotin in vivo as measured by the per cent of the total administered radioactivity found in non-protein fraction of plasma was remarkably decreased following the ligation of celiac artery or of renal vessels.However, the least degradation of I¹³¹-Parotin in vivo was observed in the group where portal vein as will as celiac, superior mesenteric and inferior mesenteric arteries were ligated.
Significantly large retention of radioactivity was found in liver after the ligation of celiac artery and also after the ligation of renal vessels.It was suggested that very close correlations on the degradation and distribution of I¹³¹-Parotin exist between liver and kidney which were recognized to be the main sites of degradation of the labeled Parotin in vivo.

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The in vitro degradation of I¹³¹-labeled Parotin as well as similarly labeled bovine serum albumin, pituitary growth hormone, and casein by several tissue homogenates of rat, was studied by measuring the increase of the radioactivity in the non-protein fraction of the incubation mixture and also by employing the quantitative paperchromatographic analysis.
I¹³¹-labeled Parotin, growth hormone and casein were degraded with remarkable rapidity by submaxillary gland homogenate.And some appreciable degradation of these three radioiodinated proteins was observed in case of kidney, spleen, parotid gland, muscle, testis, liver and pancreas homogenates. By paperchromatographic analysis, the degradation of the labeled proteins by submaxillary gland homogenate and other tissue homogenates was not found to be deiodination but presumably proteolytic degradation.

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