ABSTRACT
Corticotropin releasing factor (CRF) activates the central nervous system when administered directly into the central nervous system. The autonomic and electrophysiological activation produced by central administration of CRF is paralleled by a dose-dependent locomotor activation. Perhaps of more importance for the conceptualization of CRF as a peptide involved in the organism's behavioral response to stress were the experiments showing that CRF can potentiate the effects of exposure to a novel, presumably aversive, environment. Behavioral Effects of a CRF Antagonist work has succeeded only in characterizing a behavioral action of CRF administered exogenously in amounts, at first glance, of dubious physiological relevance. Aversive situations appear much more sensitive to exogenous CRF and preliminary results suggest that these aversive states may be sensitive to administration of a weak CRF antagonist. The effects on the acquisition of conditioned suppression of the CRF antagonist α-helical CRF were examined. Alternatively, endogenous CRF may be specifically involved in the acquisition of conditioned fear.
