ICV administration of CRF blocker (CRF9-41 delta helical) reduces morphine withdrawal in rats

1. The effects of CRF9-41 delta helical on morphine withdrawal signs in rats were studied. 2. Intracerebroventricular administration of CRF9-41 delta helical 5 at 10 micrograms/kg reduced central and peripheral symptoms of the withdrawal syndrome, such as ptosis, jumping, wet dog shakes and teeth chattering; other signs remained unchanged. The effect were not dose dependent. 3. The hypothermi characteristic of the Withdrawal syndrome was reduced by CRF9-41 delta helical. 4. These results suggest that the hypothalamo pituitary adrenal(HPA) axis play an important role in the morphine withdrawal syndrome in rats.