The antagonistic effect of corticotropin-releasing factor on pentobarbital in rats.

The effects of corticotropin-releasing factor (CRF) on pentobarbital-induced sleeping time and hypothermia in rats were studied. Intraventricular administration of CRF significantly shortened the sleeping time induced by pentobarbital injection (50 mg/kg b.wt.) in a dose-dependent manner. CRF also attenuated the hypothermic effect of pentobarbital. However, peripheral administration of CRF did not affect the action of pentobarbital. alpha-Helical CRF9-41, CRF antagonist, reversed the effects of CRF. These results suggest that CRF antagonizes the effects of pentobarbital within the central nervous system.