Molecular and pharmacological studies of human vascular-type ATP-sensitive K+ channels regarding the channel kinetics

受细胞内ATP （ATP_i）抑制的钾离子通道首先在心室肌细胞中被发现，称为ATP敏感的K^+通道（即K_<ATP>通道）。随后，在许多其他组织（胰腺β细胞、骨骼肌、中枢神经元、平滑肌）中也发现了具有类似特征的K^+通道。大约十年前，K_<ATP>通道被克隆，并被发现由至少两个亚基组成：一个是形成离子传导孔的内向矫正K^+通道6家族（Kir6.x），另一个是具有多种药理特性的调节性磺脲受体（SUR）。在许多内脏和血管平滑肌的单通道记录中发现了多种类型的天然K_<ATP>通道。然而，对K_<ATP>通道亚基的分子特性研究甚少，因此确定在平滑肌中产生天然K_<ATP>通道的K_<ATP>通道组分的相对表达是很重要的。本研究的目的是研究K_<ATP>通道的分子特性，主要研究天然K_<ATP>通道的分子基础，并讨论它们与平滑肌生理功能的可能联系。我们已经准备好了原文，将很快提交给某期刊。

Potassium channels which are inhibited by intracellular ATP (ATP_i) were first identified in ventricular myocytes, referring to as ATP-sensitive K^+ channels (i.e. K_<ATP> channels). Subsequently, K^+ channels with similar characteristics have been demonstrated in many other tissues (pancreatic β-cells, skeletal muscle, central neurones, smooth muscle). Approximately one decade ago, K_<ATP> channels were cloned and were found to be composed of at least two subunits : an inwardly-rectifying K^+ channel six family (Kir6.x) which forms the ion conducting pore and a modulatory sulphonylurea receptor (SUR) that accounts for several pharmacological properties. Various types of native K_<ATP> channels have been identified in a number of visceral and vascular smooth muscles in single-channel recordings. However, little attention has been paid to the molecular properties of the subunits in K_<ATP> channels and it is important to determine the relative expression of K_<ATP> channel components which give rise to native K_<ATP> channels in smooth muscle. The aim of this study was to investigate molecular properties of K_<ATP> channels with a main interest in the molecular basis of native K_<ATP> channels and to discuss their possible linkage with physiological functions in smooth muscle. We have prepared the original article which will be submitted to some journal soon.