从单核-巨噬细胞角度探讨Kca3.1/TRPC3复合物在肾脏纤维化防治中的研究

单核-巨噬细胞（MФ）及其介导的炎症在肾脏纤维化发生发展中起着重要作用。申请者前期研究发现钙激活钾通道Kca3.1和瞬时受体电位阳离子通道TRPC3同时定位于MФ和系膜细胞（MC）上，抑制Kca3.1和/或TRPC3表达，可减少MC增殖，并调控肾脏纤维化小鼠肾局部MФ活性，但具体机制不清楚。本课题首次提出"MФ上存在Kca3.1/TRPC3复合物"概念，并设想：Kca3.1/TRPC3可能通过调控MФ介导的炎症和细胞因子分泌，延缓肾固有细胞增殖及纤维化进程。为验证之，我们将利用免疫共沉淀与膜片钳等技术，观察MФ上Kca3.1/TRPC3定位、表达及电生理学变化，明确调控Kca3.1/TRPC3对MФ表型和功能以及肾纤维化指标的影响，并分析其相关性和可能信号转导通路。以期从MФ 角度阐释Kca3.1/TRPC3在肾脏损伤修复中的作用和机制，为肾脏纤维化研究提供理论和实验依据。

Renal fibrosis is the primary pathologic change of chronic renal failure. Macrophages (MФ)-mediated inflammation plays an important role in the development of renal fibrosis.Our prioir studies find that transient receptor potential cation TRPC3 and intermediate conductance calcium-activated potassium ion channels Kca3.1 are all expressed in MФ and mesangial cell（MC）. Inhibition of Kca3.1 and/or TRPC3 can significantly increase the local amount of M2-type MФ in the renal fibrosis of mice and can reduce M1-type MФ infiltration and inherent cell proliferation. But the mechanism is not clear. It is the first time to propose the concept of "Kca3.1/TRPC3 complex", namely the Kca3.1/TRPC3 may affect the process of proliferation and renal fibrosis of inherent cells by regulating the transformation of five active isoforms of MФ and inflammation and the cytokine secretion. To test this hypothesis, we will use the co-immunoprecipitation and other techniques to determine the distribution of Kca3.1/TRPC3 in MФ, and use in vivo fibrosis model and in vitro cell culture experiments in combination with molecular biology and electrophysiology techniques to explore the effects of Kca3.1/TRPC3 mediation on the renal fibrosis, MФ activity and function and MФ electrophysiological parameters, to analyze the correlation between them, and to search for possible molecular signals. Thereby we hope to elaberate the effects of Kca3.1/TRPC3 on renal injury-repair and its mechanisms from a view of MФ, to seek new therapeutic targets for renal fibrosis prevention and to provide theoretical and experimental basis.