AIM:To investigate the effects and underlying mechanisms of resveratrol and genistein on contractile responses of rat gastrointestinal smooth muscle.METHODS:Isolated strips of gastrointestinal smooth muscle from Spraq...AIM:To investigate the effects and underlying mechanisms of resveratrol and genistein on contractile responses of rat gastrointestinal smooth muscle.METHODS:Isolated strips of gastrointestinal smooth muscle from Spraque-Dawley rats were suspended in organ baths containing Kreb's solution,and the contractility of smooth muscles was measured before and after incubation with resveratrol and genistein,and the related mechanisms were studied by co-incubation with various inhibitors.RESULTS:Resveratrol and genistein dose-dependently decreased the resting tension,and also reduced the mean contractile amplitude of gastrointestinal smooth muscle.Estrogen receptor blockades(ICI 182780 and tamoxifen) failed to alter the inhibitory effects induced by resveratrol and genistein.However,their effects were attenuated by inhibitions of α-adrenergic receptor(phentolamine),nitric oxide synthase(levorotatoryNG-nitroarginine),ATP-sensitive potassium channels(glibenclamide),and cyclic adenosine monophosphate(SQ22536).In high K+/Ca2+-free Kreb's solution containing 0.01 mmol/L egtazic acid,resveratrol and genistein reduced the contractile responses of CaCl2,and shifted its cumulative concentration-response curves rightward.CONCLUSION:Resveratrol and genistein relax gastrointestinal smooth muscle via α-adrenergic receptors,nitric oxide and cyclic adenosine monophosphate pathways,ATP-sensitive potassium channels,and inhibition of L-type Ca2+ channels.展开更多
基金Supported by Grants from the Administration of Lanzhou Scientific Technology,No.2010-1-88Gansu Natural Science Fund in China,No.1010RJZA111Natural Science Foundation of China,No.21272103 and No.81360540
文摘AIM:To investigate the effects and underlying mechanisms of resveratrol and genistein on contractile responses of rat gastrointestinal smooth muscle.METHODS:Isolated strips of gastrointestinal smooth muscle from Spraque-Dawley rats were suspended in organ baths containing Kreb's solution,and the contractility of smooth muscles was measured before and after incubation with resveratrol and genistein,and the related mechanisms were studied by co-incubation with various inhibitors.RESULTS:Resveratrol and genistein dose-dependently decreased the resting tension,and also reduced the mean contractile amplitude of gastrointestinal smooth muscle.Estrogen receptor blockades(ICI 182780 and tamoxifen) failed to alter the inhibitory effects induced by resveratrol and genistein.However,their effects were attenuated by inhibitions of α-adrenergic receptor(phentolamine),nitric oxide synthase(levorotatoryNG-nitroarginine),ATP-sensitive potassium channels(glibenclamide),and cyclic adenosine monophosphate(SQ22536).In high K+/Ca2+-free Kreb's solution containing 0.01 mmol/L egtazic acid,resveratrol and genistein reduced the contractile responses of CaCl2,and shifted its cumulative concentration-response curves rightward.CONCLUSION:Resveratrol and genistein relax gastrointestinal smooth muscle via α-adrenergic receptors,nitric oxide and cyclic adenosine monophosphate pathways,ATP-sensitive potassium channels,and inhibition of L-type Ca2+ channels.
