Induction of pseudopregnancy in the rat by reserpine and chlorpromazine.

TLDR: The pseudopregnancy response in the normal 5-day cyclic rat was tested, and 100% of the rats treated on the first day of dicstrus became pseudopregnant and gave maximal decidual responses.

Abstract: Treatment of female rats with reserpine or chlorpromazine interrupts normal estrous cycles. To establish whether this effect is related to the discharge of lutcotropin from the adenohypophysis or to the previously demonstrated inhibition of the ovulatory release of pituitary gonadotropin (LH), the pseudopregnancy response in the normal 5-day cyclic rat was tested. When single subcutaneous injections of reserpine (1 mg./kg.) or chlorpromazine (50 mg./kg.) were given to animals during the proestrous or estrous phase of the cycle, 50–60% of the animals became pseudopregnant as indicated by deciduoma formation following uterine traumatization. In contrast, 100% of the rats treated on the first day of dicstrus became pseudopregnant and gave maximal decidual responses. Prolongation of the diestrus phase also occurred in cyclic animals treated on day 2 or 3 of diestrus, but decidual formation, in response to uterine traumatization, was minimal or absent. Nembutal (35 mg./kg.) administered under similar condition...