CHANNEL REGULATION IN NORMAL/HYPERTENSIVE SMOOTH MUSCLE

这项调查的总体目标是确定离子的特征 Smooth的传导通路及其调控机制 分离正常和高血压动物的肌细胞 模特们。大部分建议的研究将在 大鼠和兔动脉平滑肌细胞的分离 肠系膜动脉或主动脉解剖环，可 获得的数量很少，但保持双极松弛 形态和激动剂诱导的收缩。膜片钳研究 (整个单元格和单声道记录)设计成 Smooth中单个钙、钠和钾通道的特征 来自正常和高血压动物的肌肉细胞。这个 血管活性受体激动剂对离子电流的调节 受体、第二信使、G 蛋白质和蛋白激酶和磷酸酶将被阐明。 荧光指示剂的荧光检测和成像 相同的细胞将阐明细胞的时间进程和同质性 对胞内钙离子和氢离子的反应。这些 将扩展方法来表征离子电导 离体肌维持过程中的通路 增殖期和非增殖期组织培养的细胞 条件。这项提议的主要优点是应用 一项系统的电生理研究 生化、生物物理和细胞生物学技术和 新鲜分离组织研究的病理学视角 培养的正常和正常动脉平滑肌细胞 自发性高血压京都自发性高血压动物模型 高血压模型与血管紧张素诱导的继发性高血压 高血压模型。该应用程序的长期目标是 了解生理机制和病理偏差 A)肌膜离子通道在调节血管中的作用 通过神经元的多次输入进行原位肌张力测定， 体液和当地产生的信号要素以及b)评估 如果发生离子电导途径的表型调制 在高血压的情况下，一种已知的情况涉及 与所研究的细胞相似的平滑肌细胞。

The overall objective of this investigation is to characterize ion conductance pathways and elucidate their regulation in smooth muscle cells isolated from normal and hypertensive animal models. Most of the proposed studies will be carried out on single arterial smooth muscle cells isolated from rat and rabbit mesenteric artery or dissected rings of aorta, which can be obtained in small number but which maintain bipolar relaxed morphology and agonist-induced contraction. Patch clamp studies (whole cell and single channel recording) are designed to characterize individual Ca2+, Na+ and K+ channels in smooth muscle cells from normal and hypertensive animals. The regulation of ionic currents by vasoactive receptor agonists and the modulation of channels by receptors, second messengers, G proteins and protein kinases and phosphatases will be elucidated. Flourometric detection and imaging of fluorescent indicators in the same cells will elucidate time courses and homogeneity of cell response with respect to cytosolic Ca2+ and H+. These approaches will be extended to characterize the ion conductance pathways occurring during maintenance of isolated smooth muscle cells under proliferative and non-proliferative tissue culture conditions. The major strength of the proposal is the application of a systematic electrophysiological investigation coupled with biochemical, biophysical and cell biology techniques and a pathological perspective to the study of freshly isolated and tissue cultured arterial smooth muscle cells from normal and hypertensive animal models such as the SHR Kyoto spontaneous hypertensive model and the angiotensin induced secondary hypertensive models. The long term goal of the application is to understand physiological mechanisms and pathological deviations of a) the role of sarcolemma ion channels in regulating vascular smooth muscle tone in situ by multiple input from neuronal, humoral and locally produced signalling elements and b) to assess if phenotypic modulation of ion conductance pathways occurs under hypertension, a condition known to involve hyperplasia of smooth muscle cells similar to those studied.