In the 1st series of experiments, male and female rats were gonadectomized at 10 days of age and simultaneously given subcutaneous syngenesio-or autotransplants of an ovary. At 25 days of age a group of the rats were subjected to stressful stimuli by making a subcutaneous croton oil pouch. Another group of the rats not exposed to stress served as controls. When they were sacrificed at 35 days of age, corpora lutea (CL) were never found in the ovarian grafts in both the control and stressed female rats. On the contrary, in 7 out of 12 stressed male hosts the grafts contained well developed CL, although those in the control animals invariably lacked them. In the 2nd series of experiments, male rats were orchidectomized on the day after birth, all the other procedures being similar to those in the preceding series. At sacrifice, CL were encountered in theovarian grafts in 6 out of 11 control rats. However, in 10 similar rats exposed to stressful stimuli, CL were formed in only one animal.These and the writer's previous findings seem to indicate that an increase in the release of GTH, LH in particular, following exposure to stressful stimuli is in some way associated with the male pattern of GTH secretion.

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Remarkable lowering of plasma cholesterol by oxandrolone administration was observed in the hypercholesteremic rats fed the high cholesterol diet but not in the rats fed the low cholesterol diet during the short experimental period. Tween 80 induced hypercholesteremia or diabetic hypercholesteremia was not prevented by oxandrolone.
Although the bile amount of the rats with bile fistulae was not influenced by the hormone administration, the biliary excretion of cholic acid and cholesterol was increased in the hormone treated group. Excretion of the radioactivity into the bile after labeled cholesterol injection was accelerated by oxandrolone. When 26-¹⁴C cholestereol was injected into the animals, more radioactivity was found in expiratory CO₂ of the oxandrolone treated rats than that of the controls. Influx of administered cholesterol from plasma to the liver was accelerated in the oxandrolone fed rats with bile duct obstruction, and outflux of endogenous cholesterol from the liver to plasma was also increased.
Cholesterol was accumulated in the liver by oxandrolone treatment when cholesterol was given simultaneously with the hormone, but the decrease of the hepatic cholesterol contents after the interruption of cholesterol feeding was promoted by the hormone administration.
Therefore, the main mechanism of the hypocholesteremic effect of anabolicsteroids is assumed to be both the acceleration of the shift of cholesterol from plasma to liver and secondary stimulation of cholesterol catabolism to bile acid.

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Human kidney tissue obtained at autopsy was homogenized in 0.15M KCl and centrifuged at 600 or 100, 000g to test the supernatants for the activity of hydrolyzing ¹²⁵Ilabelled bovine parathyroid hormone through incubation at 37°C for 1 hour and measurement of trichloroacetic acid-soluble ¹²⁵I released. PTH-hydrolyzing activity was apparently soluble and mainly located in the supernatant fraction of centrifugation at 100, 000 with the optimal pH of 4.5, unlike the rat kidney microsomal parathyroid hormone-hydrolyzing enzyme with optimal pH of 8.5. The activity per unit tissue weight slightly increased with advance in age but the total activity in both kidneys decreased with advance in age.

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Adrenalectomy in male rats slightly decreased cytochrome P-450 content in liver microsomes. The magnitude of testosterone-induced spectral change and the hydroxylating activity for testosterone by liver microsomes were markedly decreased to a similar extent in adrenalectomized male rats. Similar results were obtained, when progesterone was used as the substrate. The magnitude of testosterone-or progesteroneinduced spectral change per unit of P-450 was also decreased in the adrenalectomized males. These results suggest that the binding capacity of cytochrome P-450 for testosterone or progesterone was decreased after adrenalectomy.
In contrast to the results obtained with male rats, the binding capacity of cytochrome P-450 and the hydroxylating activity for testosterone or progesterone were not significantly decreased in the adrenalectomized females. Similarly, the binding capacity of P-450 and the hydroxylating activity for testosterone or progesterone were not significantly decreased by adrenalectomy in castrated male rats and male and female mice. However, adrenalectomy in castrated and testosterone-treated male rats produced the effects similar to those observed in the intact male rats.
These results indicate that the action of androgen to increase the binding capacity of cytochrome P-450 for steroid hormone was impaired in the adrenalectomized rats and consequently the hydroxylating activity for steroid hormones by liver microsomes was decreased.

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The administration of thyroxine increased the activity of hepatic microsomal Δ⁴-reductase for testosterone and hydrocortisone in male rats. In contrast, the thyroxine treatment slightly decreased the hepatic microsomal steroid Δ⁴-reductase activity in female rats. The Δ⁴-reductase activity of liver supernatant fraction of male and female rats was not affected by the thyroxine treatment. Castration markedly increased the microsomal steroid Δ⁴-reductase activity in male rats and treatment with testosterone depressed the steroid Δ⁴-reductase activity to the level of intact male rats. The administration of thyroxine into these castrated and castrated plus testosterone-treated rats did not increase the activity of microsomal steroid Δ⁴-reductase.
On the other hand, there was no sex difference in the activity of hepatic microsomal steroid Δ⁴-reductase in mice and the thyroxine treatment slightly decreased the steroid Δ⁴-reductase activity both in male and fenale mice.
These results suggested that the increase in the steroid Δ⁴-reductase activity in hepatic microsomes of male rats by the thyroxine treatment may be related to an impairment of androgen-induced decrease in the steroid Δ⁴-reductase activity in rat liver microsomes.

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In this paper quantitative determination of GIM in 30 apparently healthy subjects and 15 subjects with functional or organic alternations in the hypothalamic-hypophyseal axis is detailed. From the observations on the quantitati on of GIM in the varied clinical states the authors conclude that the hypothalamic region contributing GIM is different from that controlling the secretion and release of gonadotropins. This preliminary data also suggest that the quantitative determination of GIM may help to delineate hypogonadotropic hypogonadism due to pituitary disease from the hypothalamic etiology.

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In either ad libitum or restricted feeding of the high cholesterol diet for 10 days, total plasma and liver cholesterol level of the diabetic rats were remarkably higher than those of the controls. The significant difference of the plasma cholesterol between control and diabetic rats was not observed in the groups fed the low cholesterol diet, while the liver cholesterol content was more in the diabetic rats than in the controls.
The reduced biliary excretion of the total radioactivity in the diabetic rats was demonstrated using 4-¹⁴C cholesterol. Either the excretion of labeled cholic acid or cholesterol was also reduced in diabetic state, but the per cent of labeled cholesterol to total radioactivity in the bile of diabetic rats was larger than that of controls and the per cent of labeled cholic acid in the diabetic rats was less than that in controls.
The production of expiratory CO₂ following administration of 26-¹⁴C cholesterol in vivo was lower in the diabetic rats than controls, showing the decreased conversion rate of cholesterol to cholic acid in the diabetic rats.
When labeled cholic acid was administered, excretion of the radioactivity from the bile fistula was not affected in diabetic rats and the conjugation pattern of the cholic acid with taurine and glycine was not altered. It suggests that the conjugation process of cholic acid with amino acid and excretion of cholic acid was little altered between control and diabetic rats.
From these results it is concluded that the rapid progress of alimentary hypercholesteremia in the diabetic rats might be mainly accounted for the accumulation of cholesterol caused by the impairment of its conversion to cholic acid which delayed the excretion.

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The estrous cycle was examined in the mouse implanted the pellet of ergocornine or 2-Br-α-ergokryptin (CB-154), and subsequently grafted one isologous anterior pituitary. Ergocornine or CB-154 was thoroughly mixed with cholesterol at the ratio of 1:4, pelleted in the size of 5mm diameter and 2mm thickness and implanted subcutaneously to each experimental mouse. The control mice received the same size of pellets of cholesterol only. Approximately 4 weeks after pellet implantation, all mice were given one isologous pituitary graft each under kidney capsule. The vaginal smearings were made every morning throughout the experiment beginning on the day of pellet implantation.
In the control mice, the estrous cycles were not altered by cholesterol pellet implantation and the diestrous periods were prolonged by the subsequent pituitary grafting. On the other hand, the diestrous period was shortened and its elongation by pituitary grafting was markedly inhibited in the mice bearing pellets of ergocornine or CB-154. These results are attributed to the suppressing actions of these ergot alkaloids on pituitary prolactin secretion, and indicate that these drugs inhibit prolactin secretions not only from the in situ pituitary but also from the grafted pituitary.

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The effect of neonatal treatment with estrogen on the development of the reguiatory centers of pituitary gonadotrophic function appears to be diffrent according to the dose of estrogen and the length of the injection period. Daily injections of 10μg estrone to female rats for the first 10 days of life resulted in the persistent vaginal estrus. The rats were sensitive to the electrochemical (EC) stimulation of the medial preoptic area (POA) and were capable of ovulating in response to the EC stimulation of the POA (6 out of 8 rats). In contrast, after prolonged treatment with large doses of estrone (the daily dose was increased with age, 50μg being injected during the first 10 days of life, 100 μg during then ext 10 days, and 200μg from days 21 to 30), the centers for pituitary gonadotrophin secretion were more severely affected. The rats showed the persistent vaginal diestrus and their preoptic-hypothalamic system was insenlsitive to the EC stimulation. Ovulationf ailed to occur following thes timulation in all of 8 rats.

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In order to know the mechanism of copper-induced pseudopregnancy and eliminate its toxicity, radiocopper and d-PcA were used in the rat and rabbit.
The ⁶⁴Cu content in the serum and organs were determined at different times after radiocopper injection in the rat and rabbit with or without d-PcA treatment. All values must be related not only to the interval between injection and sampling but also to the organ specificity. Radiocopper concentration was highest in the liver and kidney. No relation was observed between radiocopper content and reproductive endocrine organs such as brain, pituitary, adrenals and ovaries.
D-PcA, a chelating agent for mobilizing body stores of copper, prevents induction of pseudopregnancy in rats and ovulation in rabbits by d-PcA's cupriuretic action.
From the results mentioned above, it may be explained that copper did not concentrate on specific endocrine area for the induction of pseudopregnancy and that d-PcA could prevent induction of pseudopregnancy following copper injection.

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