Effects of PGF2 alpha and of indomethacin on rabbit small and large intestinal motility in vivo.

Prostaglandin F2 alpha (PGF2 alpha) has been shown to increase contractility in the small intestine and colon in vitro, and increased mucosal prostaglandin synthesis has been reported in ulcerative colitis. The purpose of this study was to determine the effects of PGF2 alpha and of indomethacin on myoelectric and contractile activity in the rabbit ileum and colon in vivo. PGF2 alpha caused an increase in spike potential frequency and contractile activity in the terminal ileum and proximal and distal colon. Indomethacin alone increased spike potential frequency and contractile activity in the terminal ileum and proximal colon but decreased myoelectric activity in the distal colon. It is concluded that PGF2 alpha may play an important role in modulating intestinal motility, especially in the distal colon but to a lesser extent in the terminal ileum and proximal colon.