Hyperpolarization contributes to endothelium-dependent relaxations to acetylcholine in femoral veins of rats.
Hyperpolarization contributes to endothelium-dependent relaxations to acetylcholine in femoral veins of rats.
复制标题
超极化有助于大鼠股静脉中乙酰胆碱的内皮依赖性松弛。
DOI：
10.1152/ajpheart.1991.261.4.h1034
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发表时间：
1991
期刊：
影响因子：
--
通讯作者：
Vanhoutte,PM
中科院分区：
文献类型：
--
作者：
Nagao,T;Vanhoutte,PM
采用微电极技术和等长张力记录法，在大鼠股静脉研究了膜超极化对乙酰胆碱诱导的内皮依赖性舒张的贡献。乙酰胆碱引起内皮依赖性舒张和超极化的组织收缩去甲肾上腺素。在长时间暴露于乙酰胆碱（小于或等于10分钟）的松弛持续。相反，超极化随时间而下降。在硝基-L-精氨酸，一氧化氮合成的阻滞剂的存在下，松弛变得更小和短暂的，而超极化不受影响。当同时记录两个参数时，在硝基-L-精氨酸的存在下，弛豫和超极化之间存在时间关系。在收缩与60 mM K+，其中超极化不能观察到的组织中，乙酰胆碱引起的松弛和这些松弛被废除硝基-L-精氨酸。结果表明，一氧化氮和膜超极化的贡献，在大鼠股静脉乙酰胆碱诱导的内皮依赖性舒张。
The contribution of membrane hyperpolarization to endothelium-dependent relaxations induced by acetylcholine was investigated in the femoral vein of the rat using a microelectrode technique and isometric tension recordings. Acetylcholine caused endothelium-dependent relaxations and hyperpolarization in tissues contracted with norepinephrine. The relaxation was sustained during a prolonged exposure to acetylcholine (less than or equal to 10 min). In contrast, the hyperpolarization declined with time. In the presence of nitro-L-arginine, a blocker of nitric oxide synthesis, the relaxation became smaller and transient, whereas the hyperpolarization was not affected. There was a temporal relationship between the relaxation and the hyperpolarization in the presence of nitro-L-arginine, when the two parameters were recorded simultaneously. In tissues contracted with 60 mM K+, in which hyperpolarization could not be observed, acetylcholine caused relaxations and these relaxations were abolished by nitro-L-arginine. The results suggest a contribution of both nitric oxide and membrane hyperpolarization to the endothelium-dependent relaxation induced by acetylcholine in the femoral vein of the rat.