Regulation of the Autonomic Nervous System by Corticotropin-Releasing Factor
Corticotropin-releasing factor (CRF) is a 41 amino acid-containing peptide originally isolated and characterized from ovine hypothalamus on the basis of its ability to stimulate the secretion of adrenocorticotropic hormone (ACTH) from the anterior pituitary gland. Intracerebroventricular (i.c.v.) administration of CRF to the rat or dog elicits dose-related elevations of plasma epinephrine and norepinephrine concentrations. The site of origin of epinephrine secretion following i.c.v. administration of CRF is the adrenal medulla; CRF does not increase plasma concentrations of epinephrine in adrenalectomized rats. CRF is suspected to act within the central nervous system to influence the parasympathetic nervous system on the basis of the effects of this peptide on heart rate and gastric acid secretion. A physiologic role of CRF in the regulation of the autonomic nervous system is supported by data obtained in experiments utilizing CRF receptor antagonists. CRF, in addition to the regulation of pituitary ACTH secretion, may be involved in the physiologic regulation of the autonomic nervous system.