Anterior Pituitary Function in Male Rats Deprived of Dietary Protein

Anterior pituitary glands of young and adult male rats deprived of dietary protein for 5 weeks were bio-assayed in hypophysectomized rats for the presence of folliclestimulating hormone (FSH), interstitial cell stimulating hormone (ICSH), growth hormone (GH) and thyrotropic hormone (TSH). In adult rats, absence of dietary protein resulted in a moderate decrease in the hypophysial content of FSH and ICSH, whereas anterior lobes of young rats were markedly depleted of both hormones. Hypophysial FSH and ICSH were reduced equally, although in both groups of rats atrophy of the accessory reproductive organs was greater than that of the testes. The anterior pituitaries of all protein-deficient rats contained less growth hormone than those of comparable control animals. Hypophysial TSH remained unchanged from normal in adult rats on protein- free diets but was slightly decreased in young animals. Cytologic changes in the anterior pituitaries of protein-deficient rats confirmed the bio-assay findings of subnormal pituitary function.