Corticotropin releasing factor produces behavioural activation in rats

• DOI: 10.1038/297331a0
• Publication Date: 2004-11-17T21:26:17Z
• Authors: Richard E. Sutton; George F. Koob; Michel Le Moal; Jean Rivier; Wylie Vale
• Keywords: Locomotor activity

A 41-residue peptide with high potency and intrinsic activity to stimulate the secretion of corticotropin and β-endorphin by the adenohypophysis has been characterized and synthesized1,2,19. From experience with other hypophysiotropic and brain peptides3–5, and studies suggesting that CRF could act centrally to activate the sympathetic nervous system (M. Brown et al., in preparation), we considered it likely that this corticotropin/β-endorphin releasing factor (CRF) would have direct behavioural actions. We decided to investigate the effects of CRF on a simple measure of activation in the rat, locomotor activity in photocell cages. We report here that centrally injected synthetic CRF produces a dose-dependent locomotor activation in rats. This increase in activity was not produced by peripheral administration of CRF. In an open field test, rats receiving centrally injected CRF exhibited behaviour consistent with an increase in emotionality. These results suggest that CRF may have an activating action in the central nervous system independent of its effects on the anterior pituitary gland.