Gonadal Hormones and the Regression of the Corpora Lutea in the Guinea-pig

Abstract

THERE is at present little agreement about the factors involved in the regulation of the function of the corpora lutea in the ovaries of mammals. Some workers lay emphasis on the controlling influence of pituitary hormones¹, and others on the luteolytic activity of the uterus^2–4. Although the luteolytic properties of the uterus have been demonstrated by a variety of means in several species, it has been said that “the results observed from such surgical interventions are totally nonspecific and therefore to be considered as artefacts”¹. Distension of the uterus shortens the life of the corpora lutea in the guinea-pig and because the introduction of glass beads into one horn of the uterus influences only the corpora lutea in the neighbouring ovary the existence of a local mechanism which does not directly involve the pituitary gland has been suggested⁵. On the other hand, the regression of the corpora lutea seen after the administration of gonadal steroids has been attributed to the inhibition of the secretion of gonadotrophin⁶. The results of the following experiments involving the administration of oestrogen or progesterone indicate that the inhibitory effect of gonadal hormones on luteal function is exerted through the uterus and lends further support to the view that the uterus exercises a controlling influence on luteal function in the guinea-pig.