Depression by fenoprofen of the rebound contractions' elicited by vagal stimulation and arterial infusion of ATP in the rabbit stomach in vivo

In the atropine-treated rabbit, vagal stimulation, arterial infusion of ATP or vasoactive intestinal peptide (VIP) caused gastric relaxation. At the end of either vagal stimulation or ATP infusion, but not after VIP, the gastric inhibitory responses were abruptly interrupted by 'rebound contractions'. Administration of fenoprofen depressed or abolished the rebound contraction, thus transforming the brisk relaxant response, elicited by vagal stimulation or ATP, into long-lasting relaxation. Indomethacin depressed the rebound contractions only at high doses and this effect was not always reproducible.