过敏性哮喘豚鼠气道平滑肌三磷酸腺苷敏感钾通道动力学特性  

Dynamics characteristics of adenosine triphosphate-sensitive potassium channels in allergic asthmatic guinea-pig airway smooth muscle cells

作　　者：孙红宇[1] 邹飞[2] 李勃兴[3] 陈明[3] 

机构地区：[1]南方医科大学基础医学院生理学教研室,广东广州510515 [2]南方医科大学公共卫生与热带医学学院,广东广州510515 [3]南方医科大学基础医学院神经生物学教研室,广东广州510515

出　　处：《新乡医学院学报》2010年第4期333-335,共3页Journal of Xinxiang Medical University

基　　金：国家自然科学基金资助项目(编号:30900581)

摘　　要：目的探讨过敏性哮喘豚鼠气道平滑肌三磷酸腺苷敏感钾通道(KATP通道)的单通道动力学特性变化。方法将12只4月龄豚鼠随机分为对照组和过敏性哮喘组,每组6只。急性分离出豚鼠3～4级支气管的平滑肌细胞,应用膜片钳内面向外式记录气道平滑肌KATP通道单通道电流,并分析其动力学特性。结果当钳制电压在-60 mV时,过敏性哮喘组通道平均开放时间明显短于对照组(P<0.05);当钳制电压在-40 mV和-60 mV时,过敏性哮喘组通道平均关闭时间明显长于对照组(P<0.05)。当钳制电压在-40 mV和-60 mV时,过敏性哮喘组通道开放概率明显低于对照组(P<0.01)。结论过敏性哮喘时KATP通道单通道动力学特性发生改变,使气道平滑肌对抗去极化能力减弱,可能是气道高反应性中平滑肌收缩反应增强的重要原因之一。Objective To analyze the changes in dynamics characteristics of single channel currents of adenosine triphosphate-sensitive potassium channels（KATP channels）in guinea-pig airway smooth muscle cells underlying allergic asthma.Methods Twelve four-month old guinea pigs were randomly divided into control group and experimental allergic asthma group,six in each group.Smooth muscle cells from 3 to 4 generation bronchi of guinea pig were acutely dissociated.Inside-out model of patch clamp technique was used to record the single channel currents of KATP channels,and the dynamics characteristics of the currents were analyzed.Results The mean open time of KATP channels in asthma group was shorter than in control group at-60 mV（P0.05）.The mean close time of KATP channels in asthma group were longer than in control group at-40 mV and-60 mV（P0.05）.The open probabilities of KATP channels in asthma group were lower than in control group at-40 mV and-60 mV（P0.01）.Conclusion Allergic asthma results in an inhibition of KATP channels activities,which may reduce the antagonizing ability of airway smooth muscle cells to depolarization and then lead to high contraction response of airway smooth muscle cells in bronchial hyperresponsiveness.

关 键 词：三磷酸腺苷敏感钾通道 过敏性哮喘 气道平滑肌 

分 类 号：R332.2[医药卫生—人体生理学]