Kuriyama H, Kitamura K, Itoh T, Inoue R
Seinan Jogakuin University, Kokura-Kita, Fukuoka, Japan.
Physiol Rev. 1998 Jul;78(3):811-920. doi: 10.1152/physrev.1998.78.3.811.
Visceral smooth muscle cells (VSMC) play an essential role, through changes in their contraction-relaxation cycle, in the maintenance of homeostasis in biological systems. The features of these cells differ markedly by tissue and by species; moreover, there are often regional differences within a given tissue. The biophysical features used to investigate ion channels in VSMC have progressed from the original extracellular recording methods (large electrode, single or double sucrose gap methods), to the intracellular (microelectrode) recording method, and then to methods for recording from membrane fractions (patch-clamp, including cell-attached patch-clamp, methods). Remarkable advances are now being made thanks to the application of these more modern biophysical procedures and to the development of techniques in molecular biology. Even so, we still have much to learn about the physiological features of these channels and about their contribution to the activity of both cell and tissue. In this review, we take a detailed look at ion channels in VSMC and at receptor-operated ion channels in particular; we look at their interaction with the contraction-relaxation cycle in individual VSMC and especially at the way in which their activity is related to Ca2+ movements and Ca2+ homeostasis in the cell. In sections II and III, we discuss research findings mainly derived from the use of the microelectrode, although we also introduce work done using the patch-clamp procedure. These sections cover work on the electrical activity of VSMC membranes (sect. II) and on neuromuscular transmission (sect. III). In sections IV and V, we discuss work done, using the patch-clamp procedure, on individual ion channels (Na+, Ca2+, K+, and Cl-; sect. IV) and on various types of receptor-operated ion channels (with or without coupled GTP-binding proteins and voltage dependent and independent; sect. V). In sect. VI, we look at work done on the role of Ca2+ in VSMC using the patch-clamp procedure, biochemical procedures, measurements of Ca2+ transients, and Ca2+ sensitivity of contractile proteins of VSMC. We discuss the way in which Ca2+ mobilization occurs after membrane activation (Ca2+ influx and efflux through the surface membrane, Ca2+ release from and uptake into the sarcoplasmic reticulum, and dynamic changes in Ca2+ within the cytosol). In this article, we make only limited reference to vascular smooth muscle research, since we reviewed the features of ion channels in vascular tissues only recently.
内脏平滑肌细胞（VSMC）通过其收缩 - 舒张周期的变化，在维持生物系统的内环境稳定中发挥着至关重要的作用。这些细胞的特征因组织和物种的不同而有显著差异；此外，在给定组织内通常也存在区域差异。用于研究VSMC中离子通道的生物物理方法已从最初的细胞外记录方法（大电极、单或双蔗糖间隙法）发展到细胞内（微电极）记录方法，再到从膜片段进行记录的方法（膜片钳，包括细胞贴附式膜片钳方法）。由于这些更现代的生物物理方法的应用以及分子生物学技术的发展，目前正在取得显著进展。即便如此，我们对于这些通道的生理特征及其对细胞和组织活性的贡献仍有许多需要了解的地方。在这篇综述中，我们详细探讨VSMC中的离子通道，特别是受体操纵的离子通道；我们研究它们与单个VSMC收缩 - 舒张周期的相互作用，尤其是它们的活性与细胞内Ca2 + 运动和Ca2 + 稳态相关的方式。在第二和第三节中，我们主要讨论主要源自微电极使用的研究结果，尽管我们也介绍了使用膜片钳方法完成的工作。这些章节涵盖了关于VSMC膜电活动（第二节）和神经肌肉传递（第三节）的工作。在第四和第五节中，我们讨论使用膜片钳方法对单个离子通道（Na +、Ca2 +、K + 和Cl -；第四节）以及各种类型的受体操纵离子通道（有或没有偶联的GTP结合蛋白以及电压依赖性和非依赖性；第五节）所做的工作。在第六节中，我们查看使用膜片钳方法、生化方法、Ca2 + 瞬变测量以及VSMC收缩蛋白的Ca2 + 敏感性对VSMC中Ca2 + 作用所做的工作。我们讨论膜激活后Ca2 + 动员发生的方式（Ca2 + 通过表面膜的流入和流出、从肌浆网的释放和摄取以及细胞溶质内Ca2 + 的动态变化）。在本文中，我们仅有限地提及血管平滑肌研究，因为我们最近才综述了血管组织中离子通道的特征。
