Action of testosterone propionate on the gonadotrophic function of the pituitary gland in the cyclic female rat.
Four-day cyclic female rats were injected with 5 mg testosterone propionate (TP) at dioestrus II at 10.00. A blockade of ovulation was observed on the morning of oestrus in most of these animals. No LH surge occurred in the afternoon of pro-oestrus. By contrast the size of follicles exceeding 400 micrometer in diameter did not differ in the afternoon of pro-oestrus in TP-treated and control females. Moreover both the number of follicles and the blood FSH concentration appeared to be higher at 14.00 on pro-oestrus in TP-treated than in control females. The effects of TP in vivo are thus in agreement with the observations which showed that TP caused a blockade of LH release and the maintenance of FSH release in vitro.
D000818:Animals; D004031:Diestrus; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood / Q000378:metabolism*; D007986:Luteinizing Hormone / Q000097:blood / Q000378:metabolism*; D006080:Ovarian Follicle / Q000187:drug effects; D010060:Ovulation / Q000187:drug effects; D010903:Pituitary Gland, Anterior / Q000187:drug effects* / Q000378:metabolism; D011247:Pregnancy; D011359:Proestrus; D011863:Radioimmunoassay; D051381:Rats; D013739:Testosterone / Q000494:pharmacology*
D013739:Testosterone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone