The prolactin, growth hormone, and cortisol responses to insulin-induced hypoglycemia in anorexia nervosa

Abstract

Plasma levels of prolactin and their response to insulin-induced hypoglycemia or to the thyrotropin-releasing hormone (TRH) were measure in 17 females with primary anorexia nervosa when they were 54.9-73.2% of ideal body weight (IBW) (group 1) and in 15 cases during or after weight gain (75.1-100.4% of IBW, group 2). Basal prolactin concentrations were well within the normal range (less than 25 ng/ml) in all anorectic patients except in one patient who had a value of 42.3 ng/ml. Prolactin response to insulin-induced hypoglycemia was markedly impaired or absent in 16 out of the patients in Group 1 but improved dramatically in 9 of the patients in Group 2. Direct stimulation of the pituitary with TRH, however, produced a prolactin release in all anorectic patients studied. Plasma GH response to insulin-induced hypoglycemia was impaired in 12 of the patients in group 1 and 12 of the patients in group 2. Plasma cortisol response to insulin-induced hypoglycemia was impaired in 11 of the patients in group 1 and in 3 of the patients in group 2. These findings indicate that the hypothalamic function in anorectic patients is altered.