EFFECTS OF LACTOGENIC AND GONADOTROPIC HORMONES ON HYPOPHYSECTOMIZED PREGNANT RATS

Publisher Website
Google Scholar
Abstract
Rats were hypophysectomized 1 to 9 days after mating and injected with various doses of a hypophyseal gonadotrophin (synergist), lactogenic hormone, or pregnant mare serum (PMS). Adm. of synergist or lactogen, but not of PMS, nrevented interruption of pregnancy in a number of animals hypophysectomized before or after the expected time of implantation of ova. Treatment maintained pregnancy for varying periods of time. In some animals resorption of embryos took place within a few days after treatment was begun; in other animals pregnancy was terminated by delivery of postmature fetuses. Fetuses were retained as late as 28 days post coitum. Animals which carried fetuses gained in body wt., but they rapidly lost wt. if pregnancy were terminated by delivery or resorption. The mammary glands of all treated rats in which fetal development occurred were highly stimulated, and the alveoli were distended with secretion. The results indicate that gonadotrophic substances may not only cause corpora lutea to form, but may also stimulate them to secrete.