Effects of prostaglandins E2 and F2 alpha on electromyogram of cat colon in vitro.

Prostaglandins cause diarrhea, and their production by the gut increases in diarrheal states. We studied the effects of PGF2 alpha and PGE2 on the electromyogram recorded from the cat colon in vitro to determine if these prostaglandins might produce electromyographic changes similar to those seen in diarrheal states. PGF2 alpha decreased slow wave frequency and uncoupled slow wave propagation in the proximal colon. It increased the frequency of migrating spike bursts. PGE2 had no effect on slow waves, but increased the frequency of the migrating spike burst. PGF2 alpha produced electromyographic changes similar to those recorded from the colon of cats with spontaneous diarrhea or after exposure to diarrhea-producing agents such as ricinoleate or quinidine. Some diarrhea-producing agents are likely to act by increasing prostaglandin production.