Phospholipase C contracts visceral smooth muscle.
Phospholipase C added into the muscle bath (0.2-1.5 units/ml) contracted the guinea-pig taenia coli in a concentration-dependent manner. The fully developed contraction appeared within second, like the contractile effect evoked by 5 microM acetylcholine. Pharmacochemical dissection (using phospholipase D, indomethacin, neomycin, Li+, phorbol ester and oleoyl-acetyl-glycerol) showed that the contractions induced by exogenous phospholipase C are mediated by inositol trisphosphate, not by diacylglycerol. Thus, direct evidence is provided for the key role of the phospholipase C/inositol-trisphosphate system in smooth muscle contraction.
D000818:Animals; D002432:Cecum / Q000187:drug effects; D002712:Chlorides / Q000494:pharmacology; D003106:Colon / Q000187:drug effects; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008094:Lithium / Q000494:pharmacology; D018021:Lithium Chloride; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects*; D009355:Neomycin / Q000494:pharmacology; D010738:Type C Phospholipases / Q000494:pharmacology*
D002712:Chlorides; D008094:Lithium; D010738:Type C Phospholipases; D018021:Lithium Chloride; D009355:Neomycin