Abdominal Surgery‐ and Trephination‐Induced Delay in Gastric Emptying is Prevented by Intracisternal Injection of CRF Antagonist in the Rat

Abstract

The role of endogenous corticotropin‐releasing factor (CRF) in mediating surgery‐induced delay in gastric emptying of a noncaloric solution was studied in rats using intracisternal injection of a CRF antagonist, α‐helical CRF9‐41. Intracisternal injections and surgery (abdominal or trephination) were performed under ether anesthesia. After rats recovered from anesthesia, a methylcellulose phenol red solution was administered oropharyngeally and gastric emptying was measured 20 minutes later. Laparotomy, followed by exteriorization of the cecum for 60 seconds (abdominal surgery), trephination, intracisternal injection, of CRF (130 pmol), and ether exposure alone for 120 to 140 or 70 to 80 seconds, inhibited gastric emptying by 83%, 81%, 60%, 56%, and 32%, respectively, as compared with an untreated control group. Intracisternal injection of α‐helical CRF9‐41 significantly enhanced gastric emptying by 27% and prevented by 79% to 87% the inhibition of gastric emptying induced by intracisternal injection of CRF and ether exposure (70–80 s) alone or combined with abdominal surgery. Intracisternal injection of the CRF antagonist (13–26 nmol) dose dependently prevented ether‐induced (120–140 s) and trephination‐induced inhibition of gastric emptying. These results suggest that central CRF may be involved in mediating the acute postoperative delay in gastric emptying.