title: Antagonism by fenamates of prostaglandin action in guinea-pig and human alimentary muscle.
abstract: 1 Low concentrations of meclofenamate, flufenamate or mefenamate had little effect on contractions in response to acetylcholine in any tissue studied. 2 Sodium meclofenamate potently antagonized contractions of guinea-pig ileum longitudinal muscle to prostaglandin E2 (PGE2), PGF2 alpha or PGD2. 3 In guinea-pig colonic longitudinal muscle, contractions to PGE2 were reduced by sodium meclofenamate, but contractions of the longitudinal or circular muscle to PGF2 alpha or PGD2 were less effectively inhibited. 4 In human gastrointestinal longitudinal muscle, sodium meclofenamate or flufenamate potently inhibited contractions to PGF2 alpha, but not to PGE2. 5 Sodium mefenamate or mefenamic acid, even in high concentrations, had little effect on contractions to PGF2 alpha, but tended to inhibit PGE2-induced contractions of human gastrointestinal longitudinal muscle. 6 The therapeutic advantages of prostaglandin synthesis inhibitors which also antagonize responses to certain prostaglandins are discussed.
mesh_terms: D000818:Animals; D004064:Digestive System / Q000187:drug effects*; D005439:Flufenamic Acid / Q000494:pharmacology*; D006168:Guinea Pigs; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008469:Meclofenamic Acid / Q000494:pharmacology*; D008528:Mefenamic Acid / Q000494:pharmacology*; D009119:Muscle Contraction / Q000187:drug effects*; D009129:Muscle Tonus / Q000187:drug effects; D011448:Prostaglandin Antagonists / Q000494:pharmacology*; D011453:Prostaglandins / Q000494:pharmacology; D062367:ortho-Aminobenzoates / Q000494:pharmacology*
chemical_list: D011448:Prostaglandin Antagonists; D011453:Prostaglandins; D062367:ortho-Aminobenzoates; D008528:Mefenamic Acid; D008469:Meclofenamic Acid; D005439:Flufenamic Acid