Abstract
It has been shown that 2 antagonistic hormones are present in the anterior pituitary gland, one causing growth and maturation of follicles and the other atresia of follicles in the ovary of the guinea pig; the former predominates in the anterior pituitaries of rabbit, rat and guinea pig and the latter in the glands of cattle, sheep and hog, at least in the state in which these latter are accessible to us for experimentation. 1 , 2 , 3 When as the result of the action of the first hormone the follicle has reached full size and matured, either ovulation and formation of true corpora lutea may take place or there may be ingrowth of vessels and connective tissue into the granulosa and formation of pseudocorpora lutea not associated with ovulation. 2 There occurs a third effect common to the substances in which both of these hormones are found, a transformation of theca interna, and probably also of connective tissue cells into strands of interstitial gland and into interstitial gland bodies, which transformation is found in the course of follicular atresia. 4 Transitions from the interstitial gland bodies to small pseudocorpora lutea occur and such pseudocorpora lutea may be seen especially after several injections of extract of cattle anterior pituitary into the guinea pig. Smaller amounts of pseudolutein tissue may furthermore be produced in the ovary of the guinea pig in follicles undergoing connective tissue atresia as a result of cattle anterior pituitary extracts. However, we do not wish to exclude the possibility that under certain conditions also granulosa may participate in the formation of these structures, at least in a limited way.
Under these conditions it was of interest to study the combined effect of these 2 antagonistic principles in the guinea pig. Such investigations were begun several years ago; at that time we combined injections of extract of cattle anterior pituitary with implantations of guinea pig anterior pituitary and in one case with implantation of anterior pituitaries of rabbit. 4
Get full access to this article
View all access options for this article.