脉络宁血管舒张作用的实验研究

目的观察脉络宁注射液的血管作用并探讨其可能的机制。方法采用大鼠离体胸主动脉环张力测定法。结果脉络宁注射液能明显舒张由苯肾上腺素(PE)或氯化钾(KCI)预收缩的大鼠主动脉环,其血管舒张作用并不依赖血管内皮。脉络宁注射液对缺氧引起的血管收缩没有抑制作用。对去内皮的血管环,在无钙溶液中,脉络宁注射液能够抑制PE(10-6mol/L)诱导的短暂收缩。TEA敏感性K+通道阻断剂四乙胺(TEA,5×10-3mol/L)可部分抑制脉络宁注射液的舒血管作用。ATP敏感性K+通道阻断剂格列苯脲(Gly,10-3mol/L)并不能抑制脉络宁注射液的舒张血管作用。结论脉络宁注射液的非内皮依赖性血管舒张作用机制可能是通过抑制细胞外钙内流、胞内内质网钙离子释放而起作用。TEA敏感性K+通道的激活部分参与了脉络宁注射液的舒血管作用。ATP敏感性钾通道可能并没有参与。脉络宁注射液不能抑制缺氧引起的血管收缩。

Vascular Effect of Mailuoning on Rat Thoracic Aorta Rings

Objective To investigate the relaxant effect of mailuoning on vascular rings and the underlying mechanisms.Methods Study was performed with the model of isolate rat thoracic aorta rings in organ bath,and the constraction changes were recorded.Results Mailuoning obviously vasodilated rat aortic rings preconstricted by PE or KCL,which was endothelium-independent.Mailuoning had no effect on aortic rings constricted by hypoxia.Mailuoning inhibited instant constractions of PE(10(-6) mol/L) on endothelium-removed aortic rings in Ca(2 )-free medium.The relaxant effect was partly inhibited by tetraethylammonium(TEA), a king of K channel blockade,while another K channel blockade glibenclamide(Gly) had no such effect.Conclusions The relaxant effect of Mailuoning on rat thoracic aorta rings was endothelium-independent.Mailuoning inhibited Ca(2 )-induced contraction by reducing Ca(2 ) influx and intracellular Ca(2 ) release.The activation of TEA-dependent K channel partly contribute to the relaxant effect of mailuoning while the ATP-dependent K channel may not take part in.Mailuoning has no effect on hypoxia-induced aortic rings constriction.