血压调控KCa2.3离子通道对瓣膜性房颤影响的分子动力学模拟  

Molecular Dynamics Simulation of the Effect of Blood Pressure Regulation of KCa2.3 ion Channel on Valvular Atrial Fibrillation

作　　者：刘岩[1] 孙毅 张桂敏 夏健明 张洪明[1] LIU Yan;SUN Yi;ZHANG Guimin;XIA Jianming;ZHANG Hongming(Department of Force,Kunming University of Science and Technology,Kunming 650500,China;Fuwai Yunnan Cardiovascular Hospital,Kunming 650032,China)

机构地区：[1]昆明理工大学力学系,云南昆明650500 [2]云南阜外心血管病医院,云南昆明650032

出　　处：《贵州大学学报（自然科学版）》2022年第1期36-42,共7页Journal of Guizhou University:Natural Sciences

基　　金：国家自然科学基金资助(81960072);云南省应用基础研究计划资助项目(2018FE001,202001AY070001)。

摘　　要：KCa2.3离子通道蛋白是分布在心肌细胞上的生物大分子,其主要作用是控制细胞内钾离子外流速率,前人试验研究发现该分子的表达情况与血压大小有关,但未给出数量级关系。为深入探究KCa2.3离子通道蛋白与血压之间的关系,本文建立了KCa2.3离子通道蛋白模型,运用分子动力学模拟(molecular dynamics, MD)方法对其进行深入分析,将KCa2.3离子通道蛋白置于不同压力环境下进行了扩散性、体系自由能、稳定性和分子聚集特性分析,计算发现:当压力处于120~150 mmHg时,通过KCa2.3离子通道蛋白的钾离子相对其他压力环境下少,说明压力对KCa2.3离子通道蛋白有一定的影响,二者之间的关系呈"U"型,当压力处于120~150 mmHg时,通过KCa2.3离子通道蛋白的钾离子较少,所引起的生物电流较小;不同环境下体系的势能均处在某一个区间内,说明钾离子外流过程中未发生化学反应,仅为各原子之间势能的转移;不同环境下KCa2.3离子通道蛋白均未发生严重变形,说明压力对KCa2.3离子通道蛋白的稳定性没有影响;钾离子在通过KCa2.3离子通道蛋白时未出现聚集现象。KCa2.3 ion channel protein is a biomolecule distributed in cardiomyocytes, and its main role is to control the intracellular potassium ion outflow rate. Previous experimental studies have found that the expression of this molecule is related to blood pressure, but the order of magnitude relationship has not been given. In order to further explore the relationship between KCa2.3 ion channel protein and blood pressure, the KCa2.3 ion channel protein model was established and analyzed by Molecular Dynamics(MD) method. The diffusion, system free energy, stability and molecular aggregation characteristics of KCa2.3 ion channel protein were analyzed under different pressure environments. The calculation results show that: When the pressure is 120~150 mmHg, less potassium ions pass through KCa2.3 ion channel protein compared with other pressure environments, indicating that pressure has a certain influence on KCa2.3 ion channel protein, and the relationship between the two is in the shape of "U". When the pressure was 120~150 mmHg, less potassium ions passed through KCa2.3 ion channel protein, resulting in less biological current;The potential energy of the system in different environments is all in a certain interval, indicating that no chemical reaction occurs in the process of potassium ion outflow, only the transfer of potential energy between atoms;KCa2.3 ion channel protein did not undergo serious deformation under different environments, indicating that pressure had no effect on the stability of KCa2.3 ion channel protein;There is no aggregation of potassium ions through KCa2.3 ion channel protein.

关 键 词：生物大分子 KCa2.3离子通道 分子动力学模拟 钾离子外流 

分 类 号：Q61[生物学—生物物理学] Q71