Comparative histochemical study of the enzyme changes in the ovary and uterus of mammals with special references to steroidogenesis.

A comparative study of the enzymes delta5-3beta-HSD, cytochrome oxidase and peroxidase has been made in the ovaries and uterus of mammals (mouse, guinea pig, cat and dog) during various reproductive phases. The granulosa cells of developing follicles, hypertrophied interstitial cells of thecal origin and the luteal cells show intense delta5-3beta-HSD and cytochrome oxidase activity. Peroxidases are found to be present in the corpus luteum and the epithelial cords of thecal origin. delta5-3beta-HSD and cytochrome oxidase activity is localized to the endometrium and myometrium of mature and pregnant uterus of mouse and guinea pig, while peroxidase is seen only in the decidua and endometrial glands of pregnant animals. The significance of these enzymes is discussed in relation to the cellular basis of luteinization and steroid hormone synthesis.