Ovariotomized and ovariotomized-hypophysectomized adult female newts, Triturus pyrrhogaster, were given intraperitoneal injections of progesterone. The development of the oviducts was not at all stimulated by progesterone in these animals, the oviducal epithelial cells remained atrophic as in non-injected controls. However, histochemical studies revealed that in a majority of the progesteronetreated animals, the oviducts exhibited a definitely stronger reaction of alkaline phosphatase in the cytoplasm of the epithelial cells than in non-injected operated newts. It seems highly probable that progesterone directly activates alkaline phosphatase in the epithelial cells of the oviducts. The findings were discussed in relation to the effects of progesterone on the ovulation in amphibians.

View full abstract

In persistent-diestrous rats secured by continued injections of estrogen for the first 30 days of the postnatal life, the ovarian ascorbic acid depleting potencies of the anterior pituitary and of the hypothalamus were significantly decreased as compared with those in normal females. The prolonged treatment with estrogen seems to have brought about an irreversible derangement in the regulatory mechanism of the production and release of LH-RF by the hypothalamus.

View full abstract

For induction of ovulation, HCG injection following PMS injection was effective. When eleven animals were injected with 1, 500 IU of PMS on the 16th to 20th day of the sexual cycle and then 500 or 1, 000 IU of HCG on the 2nd to 8th day after the last PMS injection (on the first day of estrus for the most part), 10 to 48 follicles, or 25.5 on the average, developed in both ovaries of each animal. In these ovaries, the number of ovulation points was in a range of 6 to 26, or 13.3 on the average. Therefore, the ovulation percentage was in a range of 27.2 to 80.0%, 53.2% on the average. Of ten animals injected with PMS on the 18th to 21st day of the sexual cycle, two showed no estrus. In the remaining eight animals, estrus recurred on the 2nd to 5th day or the 2.5th day on the average, after the last injection. The duration of estrus ranged from 1 to 5 days, 2.5 days on the average. In other nine animals injected with HCG following PMS injection, the duration of estrus was 1 to 2 days, 1.3 days on the average. This indicates that HCG injection had an effect of shortening the duration of estrus. This effect is probably related to its effect of inducing ovulation.

View full abstract