Neuroendocrine Effects of Intravenous Ovine Corticotropin-Releasing Factor and Human Growth Hormone-Releasing Factor in Affective Disorder Patients and Normal Controls

A wide variety of neuroendocrine abnormalities have been reported in affective disorder patients. Probably the most extensively studied have been hypothalamic-pituitary-adrenal (HPA) activation and dexamethasone resistance. In addition, an elevated 24-h pituitary growth hormone secretion has been reported in depressed patients. Reduced pituitary growth hormone responses to central nervous system (CNS) probes have been reported in depressed patients, particularly in response to the noradrenergic agent clonidine. The sequencing and availability of corticotropin-releasing factor (CRF) and growth hormone-releasing factor (GRF) allow direct testing of pituitary responses to these neuropeptides in affective disorder patients. Our findings to date confirm the reports by Gold and colleagues1 and Holsboer and colleagues2 of an attenuated ACTH response to intravenously administered ovine CRF in depressed patients. In addition, we preliminarily report an attenuated growth hormone response to intravenous human GRF in depressed patients.