银杏叶水提取物对大鼠离体胸主动脉环的舒张作用

Vasodilative effects of water extract of the Ginkgo biloba leaves on thoracic aorta ring of rats in vitro

[目的]探讨银杏叶水提取物对大鼠离体胸主动脉环的舒张作用及其机制.[方法]建立大鼠离体主动脉环灌流模型,观察银杏叶水提取物对分别经1μmol/L苯肾上腺素及5-HT预收缩的内皮完整血管环和去内皮血管环的舒张作用,并观察左旋硝基精氨酸甲酯(L-NAME)及亚甲蓝预处理对银杏叶水提取物的舒张血管作用的影响.[结果]银杏叶水提取物对大鼠离体内皮完整的胸主动脉环具有浓度依赖性的舒张作用;L-NAME和亚甲蓝预处理可明显抑制银杏叶水提取物的舒张作用.[结论]银杏叶水提取物对大鼠离体胸主动脉环具有内皮依赖性舒张血管作用,其可能机制是通过血管内皮细胞鸟苷酸环化酶途径介导.

OBJECTIVE To study the vasodilative effects and its mechanisms of water extract of the Ginkgo biloba leaves for thoracic aorta ring of rats in vitro.METHODS The perfusion model of thoracic aorta ring of rats was established in vitro to observe the dilative effects of water extract of the Ginkgo biloba leaves for integrated endothelium and des-endothelium vascular ring pre-constricted by 1 μmol/L phenylephrine（PE）and 1,5-hydroxytryptamine（5-HT）and the effects of vasodilation of water extract of the Ginkgo biloba leaves pretreated with the L-NAME and methylthioninium chloride.RESULTS The water extract of Ginkgo biloba leaves for integrated endothelium thoracic aorta ring of rats in vitro had a concentration-dependent dilation,and pretreatment with the L-NAME and methylthioninium chloride could obviously inhibit the vasodilation.CONCLUSION The water extract of Ginkgo biloba leaves has endothelium-dependent vasodilative effects of thoracic aorta ring of rats in vitro,and the effects may be mediated by the guanylyl cyclase pathway of vascular endothelial cells.