The effect of androgenic compounds on the histological structure of the pituitary in the castrated rat

Abstract

It is known that the administration of certain hormone preparations will prevent the development of the characteristic histological changes in the anterior pituitary of the castrated male rat. This has been effected by implants of testicular and ovarian tissue, injection of testis extracts and of female hormones; the literature has been adequately reviewed by Severinghaus, Engle and Smith (1932) and Nelson and Gallagher (1936). Some of the crystalline male hormone preparations now available have also been used with success. Schoeller, Dohrn and Hohlweg (1936) compared the amounts of testosterone, testosterone propionate, androsterone and oestradiol benzoate required to prevent the appearance of changes for 15 days after castration in immature and adult rats of both sexes. They found that in the adult male a daily dose of 0·15 γ of oestradiol benzoate, 150 γ of testosterone propionate, 300 γ of testosterone, and 2000 γ of androsterone was successful. In the adult female more oestradiol benzoate is necessary (0·3 γ ), but less androsterone (1500 γ ): the doses of testosterone and testosterone propionate are the same for the two sexes. In immature animals (29-33 g. body weight), the doses necessary are considerably smaller. Wolfe and Hamilton (1937), using a standard dose of 500 γ daily for 10 days, found that testosterone, testosterone propionate and testosterone acetate maintained the normal pituitary structure in immature males, and that testosterone acetate and oestrone were successful in immature females. Another type of experiment, the restoration of the pituitary to normal in animals castrated for several weeks, has been carried out by several investigators. Ovarian and testicular implants and injections of testis extracts and female hormones have been used with varying success. Korenchevsky, Dennison and Simpson (1935) report that androsterone, androstanediol and oestrone will restore the hypertrophied pituitary of the castrated rat to the normal weight, and cause partial restoration of the histological structure. With testosterone and testosterone propionate there was no definite return to normal weight (Korenchevsky, Dennison and Eldridge 1937).