ICV-CRH alters stress-induced freezing behavior without affecting pain sensitivity

Pharmacol Biochem Behav. 1988 Aug;30(4):801-7. doi: 10.1016/0091-3057(88)90103-7.


Freezing is an adaptive response often induced by stressful, fear-eliciting stimuli. Three experiments with rats investigated the effects of intracerebroventricular (ICV) administration of corticotropin-releasing hormone (CRH) on freezing behavior and pain sensitivity. Experiments 1 and 3 demonstrated that ICV-CRH (300 ng) enhanced shock-elicited freezing. In Experiment 1, ICV-CRH also enhanced recovery from shock-elicited freezing, suggesting that the peptide has a biphasic effect. Experiments 2 and 3 established that CRH-induced freezing was not caused by heightened pain sensitivity. Interestingly, in Experiment 2, hot-plate exposure produced increased freezing that was attenuated by ICV-CRH. Thus, the direction of the ICV-CRH effect on freezing was found to depend on the nature of the stressor. These results suggest that endogenous CRH systems modulate stress-induced freezing.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cerebral Ventricles / drug effects
  • Cerebral Ventricles / physiology*
  • Cerebral Ventricles / physiopathology
  • Corticotropin-Releasing Hormone / administration & dosage
  • Corticotropin-Releasing Hormone / pharmacology*
  • Electroshock
  • Fear
  • Grooming / drug effects
  • Injections, Intraventricular
  • Motor Activity / drug effects
  • Pain / physiopathology*
  • Rats
  • Rats, Inbred Strains
  • Reference Values
  • Stereotyped Behavior / drug effects*
  • Stress, Psychological / physiopathology*


  • Corticotropin-Releasing Hormone