Arteriolar endothelial cell barrier separates two populations of muscarinic receptors.
Arteriolar endothelial cell barrier separates two populations of muscarinic receptors.
复制标题
小动脉内皮细胞屏障将两个毒蕈碱受体群分开。
DOI：
10.1152/ajpheart.1992.262.4.h1311
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Duling,BR
中科院分区：
文献类型：
--
作者：
Rivers,RJ;Duling,BR
在体外研究时，小动脉的内皮可以作为亲水性分子扩散的屏障。因此，施加到小动脉一侧的物质在到达血管壁相对侧的受体方面相对无效，除非它是脂溶性的。为了研究小动脉内皮两侧的受体群体，我们使用微量移液器将乙酰甲胆碱（MCh; 1.0 μ M）应用于戊巴比妥麻醉仓鼠的颊囊小动脉，无论是腔内还是外膜，持续5秒。MCh同样扩张小动脉，无论一侧的应用。不同的受体群体位于小动脉的两侧，这一事实表明，外膜应用的亲水性甲基东莨菪碱是无效的，在阻止的作用，腔内应用的MCh，但完全阻止的作用，abluminally应用的MCh。相反，受体的腔群体容易被外部应用的亲脂性东莨菪碱阻断。血管壁中单独和独立的受体群体表明体液和血管活性代谢物外膜来源之间的差异控制潜力。
The endothelium of arterioles can function as a barrier to diffusion of hydrophilic molecules when studied in vitro. Thus a substance applied to one side of the arteriole is relatively ineffective in reaching receptors on the opposite side of the vessel wall unless it is lipid soluble. To study the receptor populations on the two sides of the arteriolar endothelium, we used micropipettes to apply methacholine (MCh; 1.0 microM), either luminally or adventitially, for 5 s to the arterioles of the cheek pouch of pentobarbital-anesthetized hamsters. MCh equally dilated the arterioles regardless of the side of application. That different populations of receptors are located on either side of the arteriole was shown by the fact that adventitially applied hydrophilic methscopolamine was ineffective in blocking the effects of the luminally applied MCh but completely blocked the effects of abluminally applied MCh. In contrast, the luminal population of receptors was easily blocked by adventially applied scopolamine, which is lipophilic. Separate and independent populations of receptors in the vessel wall suggests the potential for differential control between humoral and adventitial sources of vasoactive metabolites.