NEONATAL CORTICOID ADMINISTRATION: EFFECTS UPON ADULT PITUITARY GROWTH HORMONE AND HYPOTHALAMIC GROWTH HORMONE-RELEASING HORMONE ACTIVITY

Abstract

ABSTRACT A single subcutaneous injection of 1 mg cortisone or cortisol acetate was given to rats during the first post-natal day. As others have reported, retardation of growth, detectable a week after birth, resulted. On reaching five to six weeks of age, treated rats had no detectable growth hormone (GH)-releasing activity in their hypothalami and little GH or thyrotrophin (TSH) activity in their pituitaries. These observations suggest that the growth retardation of rats treated neonatally with these steroids may be due, at least in part, to lack of pituitary GH resulting from impaired synthesis of GH-releasing hormone (GRH**) and also to lack of TSH.