Wettwer E
Department of Pharmacology and Toxicology, Medical Faculty, Dresden University of Technology, Dresden, Germany.
Br J Pharmacol. 2007 Nov;152(6):835-7. doi: 10.1038/sj.bjp.0707463. Epub 2007 Sep 17.
The cardiac ultrarapid outward current I(Kur), encoded by KCNA5, is of special pharmacological interest, because it is considered to be atrium-specific. I(Kur) has therefore become a target in the therapy of atrial tachyarrhythmias. However, the concept of atrium specificity is only valid if a functional I(Kur) current is in fact absent from the ventricle. However, new work has detected a I(Kur)-like current in canine ventricular myocytes, sensitive to 4-aminopyridine and suppressed by the I(Kur) blocker DPO-1, findings that support the existence of a functional ventricular I(Kur). These indications are, however, indirect and more effort is needed to clarify unequivocally the putative role of an expectedly small I(Kur) component in the ventricle.
由KCNA5编码的心脏超快速外向电流I(Kur)具有特殊的药理学意义，因为它被认为是心房特异性的。因此，I(Kur)已成为治疗房性快速心律失常的一个靶点。然而，只有当心室中实际上不存在功能性I(Kur)电流时，心房特异性的概念才成立。然而，新的研究在犬心室肌细胞中检测到一种类似I(Kur)的电流，该电流对4-氨基吡啶敏感，并被I(Kur)阻滞剂DPO-1抑制，这些发现支持了功能性心室I(Kur)的存在。然而，这些迹象是间接的，需要更多的努力来明确阐明预期较小的I(Kur)成分在心室中的假定作用。
