Physiological and behavioral effects of chronic intracerebroventricular infusion of corticotropin-releasing factor in the rat

Psychoneuroendocrinology. 1997 Jul;22(5):297-309. doi: 10.1016/s0306-4530(97)00032-2.

Abstract

The present study was conducted to investigate the long-term effects of chronic elevation of centrally circulating levels of corticotropin-releasing factor (CRF) on behavior and physiology. For this purpose ovine CRF was infused continuously for a period of 10 days into the lateral ventricle of rats with the aid of osmotic pumps (calculated CRF delivery was 4.9 micrograms/day). Changes in daily rhythms in body temperature and home cage motor activity were recorded telemetrically during the infusion period. The most prominent physiological findings were a delayed body weight gain and a long-lasting hyperthermia following CRF infusion. The peptide treatment furthermore increased adrenal weight and suppressed the weight of the thymus at the end of the experiment. Behaviorally, CRF administration elicited a short-lasting increase in activity during the light phase and an increased anxiety in an elevated plus-maze 1 week after the start of infusion. The similarities between the present results and the long-term changes previously described in behaviorally stressed rats indicate that chronically elevated levels of CRF in the brain might play an important role in the induction and persistence of stress-related behavioral and physiological disorders.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Arousal / drug effects*
  • Arousal / physiology
  • Body Temperature Regulation / drug effects
  • Body Temperature Regulation / physiology
  • Body Weight / drug effects
  • Body Weight / physiology
  • Brain / drug effects*
  • Brain / physiology
  • Circadian Rhythm / drug effects
  • Circadian Rhythm / physiology
  • Corticotropin-Releasing Hormone / pharmacology*
  • Corticotropin-Releasing Hormone / physiology
  • Infusion Pumps
  • Injections, Intraventricular
  • Male
  • Motor Activity / drug effects
  • Motor Activity / physiology
  • Rats
  • Rats, Wistar

Substances

  • Corticotropin-Releasing Hormone