短期快速心房激动对L型钙通道mRNA表达的影响

Short-term effect of rapid atrial pacing on mRNA expression of L-type Ca^(2+) channel

目的 :观察短期快速心房激动对L型钙通道α1c亚基mRNA表达的影响。方法 :新西兰大耳白兔 36只 ,随机分为 6组 ,经颈内静脉切开置入电极导管 ,于右心房分别给予 0、0 .5、1、2、4、8h快速心房起搏 ,停止起搏后立即取右心房组织 ,应用半定量逆转录 聚合酶链式反应测定L型钙通道α1c亚基mRNA表达的相对水平 ,组间比较行t检验。结果 :0 .5～ 8h不同时点的快速心房起搏使L型钙通道α1c亚基mRNA表达水平 (分别为 0 .77±0 .0 3、0 .76± 0 .0 2、0 .77± 0 .0 5、0 .73± 0 .0 4、0 .6 7± 0 .0 5、0 .6 7± 0 .0 3)逐渐下调 ,致起搏后 4h较起搏前差异有显著性意义 (P <0 .0 5 )。结论

Objective:To investigate the effect of short term atrial rapid pacing on mRNA expression of L type Ca 2+ channel α1C subunit. Methods:Thirty six rabbits were randomly divided into six groups (n=6 for each). Electrode catheter were localized in the right atrium through right internal jugular vein. Pacing was performed up to maximal atrial capture rate for 0, 0.5 , 1, 2, 4, 8 hours respectively. Right atrium tissue was obtained for measurement of L type Ca 2+ channel α1C subunit mRNA using reverse transcription polymerase chain reation (RT PCR). Results:The mRNA level of L type Ca 2+ channel α1C subunit decreased gradually and progressively during 0.5 to 8 hours pacing period. Significant difference was observed at 4 hours after the onset of pacing. Conclusion: Even short term atrial rapid excitation can decrease the mRNA level of L type Ca 2+ channel α1C subunit.