跑台训练对大鼠窦房结ClC-2型内向整流氯离子通道的影响  

Effects of Exhaustive Exercise on the ClC-2 Chloride Inward Rectifier Channel of Rat Sinoatrial Node

作　　者：薄冰[1] 

机构地区：[1]河南大学体育学院,河南开封475000

出　　处：《西安体育学院学报》2014年第6期722-727,共6页Journal of Xi'an Physical Education University

基　　金：河南省教育厅科学技术重点研究项目(14A890008)

摘　　要：目的探讨大鼠2周力竭跑台训练对心脏窦房结ClC-2型内向整流氯离子通道的影响。方法 SD大鼠分为对照组(C组)、一次力竭组(O组)、2周反复力竭组(R组),每组10只。C组大鼠不进行任何运动训练,O组大鼠在正常饲养2周后,进行1次跑台训练至力竭,R组每天进行1次跑台训练,训练时长为2周。训练组大鼠分别于运动后0 h及24 h取材,O组以O-0h和O-24h命名,R组以R-0h和R-24h命名。用实时荧光定量PCR和Western Blot技术测定ClC-2通道亚基ClC-2 mRNA及蛋白质表达,用全细胞膜片钳技术测定通道电流密度。结果(1)R-0h及R-24h组ClC-2 mRNA及蛋白质表达明显低于C组及O-0h组(P<0.01)。(2)R-0h及R-24h组ICl,ir通道电流密度分别为-2.35±0.22p A/p F和-2.61±0.20 p A/p F,比较明显地低于C组及O-0h组的3.99±0.35p A/p F和3.50±0.20p A/p F(P<0.01)。结论 2周跑台训练可引起大鼠心脏窦房结细胞膜ClC-2型内向整流氯离子通道亚基ClC-2基因表达及电流密度减少,这可能成为运动引发窦房结功能障碍的离子通道机制之一。Objective This paper discussed the subunit gene expression and current density of C1C -2 chloride inward rectifier channel in sinoatrial node after two weeks exhaustive exercise on treadmill. Methods SD rats were equally assigned into 5 groups, including 1 control groups （C group）, 2 groups undergoing single exhaustive treadmill running（ O group）, and 2 groups undergoing two weeks repeated treadmill running（ R group）, 10 rats each group. After two weeks normal feeding,single exhaus- tive treadmill running was carried out for the O group. Exhaustive treadmill running was carried out for the R groups 6 days per week for total of two weeks. The samples were drawn from rats at 0 and 24 hours after exercise. The rats of O group were named O -0h,O -24h, respectively, the rats of R group were named R-Oh ,R-2gh, respectively. The mRNA and protein expres- sion of C1C - 2 channel subunit in sinoatrial node were analyzed by real - time fluorescent quantitative PCR and Western Blot, the current density of C1C - 2 channel were analyzed by whole - cell patch clamp analysis. Results （ 1 ） The C1C - 2 mRNA and protein expression of R -Oh and R -24h group were significantly lower than that of C and O -Oh group（ P 〈0.01 ）. （2） The current density of C1C - 2 of R - Oh and R - 24h group were - 2.35± 0.22pA/pF and - 2.61 ± 0.20pA/pF respectively, significantly lower than that of C and O - 0h group 3.99 ± 0.35pA/pF and 3.50 ± 0.20pA/pF （P 〈 0.01 ）. Conclusions Two weeks exhaustive treadmill running downregulated the sinoatrial node C1C -2 gene subunit expression, along with the corresponding current ICl,ir, and may be one of the most important mechanism of exercise - induced sinoatrial node dysfunction and arrhythmia.

关 键 词：跑台训练 窦房结 ClC-2亚基 内向整流氯离子通道 

分 类 号：G804.7[文化科学—运动人体科学]