Significant circadian variations exist in the frequency of cardiac arrhythmia, but few studies have examined the relation between cardiac ion channels genes and biological clocks. We investigated this relation using suprachiasmatic nuclei lesion (SCNX) and pharmacological autonomic nervous system block (ANSB) mice. Significant 24-h variations were observed in the expression of clock genes Per2, Bmal1, and Dbp and ion channel genes KCNA5, KCND2, KCHIP2, and KCNK3 in the control mice hearts. In the SCNX mice, all genes examined lost circadian rhythm. In the ANSB mice, the expressions of the three clock genes were dampened significantly but still had circadian rhythm, whereas the four ion channel gene expressions lost rhythm. Heart rate also lost circadian rhythm in both the SCNX and ANSB mice. These results suggest that some ion channel gene expressions might be regulated by the central clock in the SCN through the ANS but not the peripheral clock in the heart.

中文翻译：

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小鼠心脏离子通道基因的昼夜节律表达可能与 SCN 的中枢时钟有关，但与心脏的外周时钟无关

心律失常的频率存在显着的昼夜节律变化，但很少有研究检查心脏离子通道基因与生物钟之间的关系。我们使用视交叉上核病变 (SCNX) 和药理学自主神经系统阻滞 (ANSB) 小鼠研究了这种关系。在对照小鼠心脏中观察到时钟基因 Per2、Bmal1 和 Dbp 以及离子通道基因 KCNA5、KCND2、KCHIP2 和 KCNK3 的表达在 24 小时内发生显着变化。在 SCNX 小鼠中，所有检测的基因都失去了昼夜节律。在 ANSB 小鼠中，三个时钟基因的表达显着减弱但仍具有昼夜节律，而四个离子通道基因表达失去节律。SCNX 和 ANSB 小鼠的心率也失去了昼夜节律。