Sun Jie, Yang Guang Ming, Tao Tao, Wei Li Sha, Pan Yang, Zhu Min Sheng
Model Animal Research Center and MOE Key Laboratory of Model Animal and Disease Study, Nanjing University.
School of Pharmacy, Nanjing University of Chinese Medicine.
J Vis Exp. 2018 Aug 20(138):58064. doi: 10.3791/58064.
The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and drugs. It is widely used in many studies on the physiological functions of vascular smooth muscle, the pathogenesis of vascular diseases such as hypertension, and the development of smooth muscle relaxant drugs. The mouse is a widely used model animal with a large pool of disease models and genetically modified strains. We introduced this method to measure the isometric contraction of mouse mesenteric artery in detail. A 1.4-mm segment of mouse mesenteric resistance artery was isolated and mounted on a myograph chamber by passing two steel wires through its lumen. After equilibration and normalization steps, the vessel segment was potentiated by a high-K solution twice prior to the contraction assay. As an example of the application of this method in drug development, we measured the relaxant effect of a novel natural substance, neoliensinine, isolated from a Chinese herb, embryos of the lotus seed (Nelumbo nucifera Gaertn.) on mouse mesenteric arteries. The vessel segments mounted on the myograph chamber were stimulated with a high-K solution. When the force tension reached a stable sustained phase, cumulative doses of neoliensinine were added to the chamber. We found that neoliensinine had a dose-dependent relaxant effect on smooth muscle contraction, thus suggesting that it bears potential activity against hypertension. In addition, as the vessel segment can survive at least 4 hours after mounting and maintain contractility induced by the high-K solution for many times, we suggest that the wire myograph system may be used for the time-consuming process of drug screening.
线肌张力描记技术用于评估血管平滑肌对去极化、G 蛋白偶联受体激动剂/抑制剂及药物的收缩性。它广泛应用于许多关于血管平滑肌生理功能、高血压等血管疾病发病机制以及平滑肌松弛药物研发的研究中。小鼠是一种广泛使用的模式动物，有大量的疾病模型和基因工程改造品系。我们详细介绍了这种用于测量小鼠肠系膜动脉等长收缩的方法。分离出一段 1.4 毫米长的小鼠肠系膜阻力动脉，通过两根钢丝穿过其管腔将其安装在肌张力描记室中。经过平衡和标准化步骤后，在收缩测定前，用高钾溶液对血管段进行两次增强。作为该方法在药物研发中应用的一个例子，我们测量了从一种中药莲子（Nelumbo nucifera Gaertn.）胚胎中分离出的一种新型天然物质新莲心碱对小鼠肠系膜动脉的舒张作用。用高钾溶液刺激安装在肌张力描记室中的血管段。当力-张力达到稳定的持续阶段时，向室中加入累积剂量的新莲心碱。我们发现新莲心碱对平滑肌收缩具有剂量依赖性舒张作用，因此表明它具有抗高血压的潜在活性。此外，由于血管段在安装后至少能存活 4 小时，并能多次维持由高钾溶液诱导的收缩性，我们建议线肌张力描记系统可用于耗时的药物筛选过程。
