【摘要】 目的研究犬右房不同部位短暂外向钾电流、L型钙电流亚单位mRNA的表达情况,探讨其在致房性心律失常中的意义。方法应用逆转录-聚合酶链反应半定量分析犬界嵴、梳状肌、右心耳的短暂外向钾电流α亚单位(Kv4.3)、β亚单位(KchIP2)及L型钙电流的α亚单位(Cav1.2)mRNA的表达量(以β-actin为内参照)。结果界嵴和梳状肌Kv4.3、KchIP2 mRNA高于右心耳(P<0.05或0.01);界嵴Cav1.2 mRNA高于梳状肌和右心耳(P均<0.05),而梳状肌和右心耳之间没有差异。结论Kv4.3、KchIP2、Cav1.2 mRNA在右房空间表达上的差异与其相应离子流在右房空间上的差异一致,可能是其离子流差异的分子基础。更多还原

【Abstract】 Objective To investigate the inhomogeneity in distribution of ion channels subunit mRNA in canine right atrium and its implication in the pathogenesis of atrial arrhythmia.Methods The mRNA expression and distribution of the transient outward current α-subunits Kv4.3,the β-subunit KchIP2 and the L-type Ca2+ current α-subunit Cav1.2 were quantified by semiquantitative reverse transcription-polymerase chain reaction in tissue sections obtained from different regions of canine right atrium including crista terminalis(CT),pectinate muscles(PM)and right atrial atrium(RAA).Results Kv4.3 mRNA was more abundant in CT than in RAA(P<0.05),KchIP2 mRNA expressed much higher in CT than in RAA(P< 0.01).Cav1.2 mRNA level was similar in PM and RAA,but significantly higher mRNA expression of Cav1.2 in CT versus PM(P<0.05).Conclusions The inhomogeneity in distribution of ion channels subunit mRNA in canine right atrium are consistent with,and shed light on the molecular basis of,well-recognized fundamental regional variation in atrial ionic currents.更多还原