Influence of prostaglandins on electrical and mechanical activities of gastric muscles of Bufo marinus.
1. Study was performed to compare the role of prostaglandins in regulating gastric contractile activity in an amphibian model, Bufo marinus, with mammalian models. 2. The prostaglandin synthesis inhibitor, indomethacin, had little effect on spontaneous mechanical activity, but increased the force and frequency of contractions stimulated by acetylcholine. 3. PGE2 reversed the effects of indomethacin and reduced the force and frequency of contractions. These effects were concentration-dependent. 4. Intracellular measurement of membrane potential demonstrated that the effects of PGE2 could be explained by basic effects on membrane potential and slow wave activity. 5. The data shown that many similarities exist between amphibian and mammalian gastric muscles in terms of the regulatory role played by endogenous PGs. It also appears that the mechanisms of PGE2 action are similar.
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D002025:Bufonidae / Q000502:physiology*; D015232:Dinoprostone / Q000494:pharmacology* / Q000502:physiology; D004357:Drug Synergism; D004558:Electric Stimulation; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects; D009119:Muscle Contraction / Q000187:drug effects*; D011930:Reaction Time / Q000187:drug effects; D013270:Stomach / Q000187:drug effects* / Q000294:innervation
D015232:Dinoprostone; D000109:Acetylcholine; D007213:Indomethacin