MAMMARY GLAND DEVELOPMENT IN HYPOPHYSECTOMIZED RATS INJECTED WITH ANTERIOR PITUITARY HORMONES AND TESTOSTERONE

Abstract

The effect of testosterone and growth hormone and of testosterone and prolactin on the mammary glands of castrated, hypophysectomized rats was studied; both male and female rats were used. Treatment with testosterone and prolactin did not produce clear lobule-alveolar development with doses used, and the type and degree of alveolar development produced by testosterone and growth hormone was similar to that produced by testosterone alone in rats with intact pituitary gland. Results indicate that growth hormone is a more important anterior pituitary factor than prolactin for alveolar development produced by testosterone in the rat mammary gland. Prolactin seems to be a more important anterior pituitary factor than growth hormone. Testosterone alone produced thickening of the mammary duct system but no lobule-alveolar development. Testosterone and growth hormone stimulated extensive alveolar development. Testosterone and prolactin stimulated a marked secretion but did not produce a clear lobule-alveolar development.