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心血管ＡＴＰ敏感性钾通道（ＫＡＴＰ）是受细胞内ＡＴＰ浓度调控的一种内向整流钾通道。在生理状态下，处于关闭状态；在缺氧的病理状态下，发挥重要的调节作用。心血管ＫＡＴＰ对钾离子通透的选择性高，在心脏和血管平滑肌中其单通道电导分别为８０和１３５ｐＳ，通道开放呈簇状并为长时间阻断状态所间隔。ＫＡＴＰ功能性结构包括通道闸门、转换亚单位、ＡＴＰ结合抑制亚单位、磷酸化位点和二磷酸核苷结合位点。ＡＴＰ对ＫＡＴＰ功能具有双向调节作用：其中配体作用是指与ＡＴＰ结合抑制亚单位结合，使通道关闭；水解依赖性作用是指在Ｍｇ２＋存在时，ＡＴＰ使转换亚单位磷酸化，使通道开放。二磷酸核苷与其特异性位点结合，不仅降低通道对ＡＴＰ的敏感性，而且可直接诱导通道开放。依对ＫＡＴＰ作用特征激活剂分３大类，其药理作用依赖于通道的功能状态，尤其是磷酸化位点、二磷酸核苷结合位点和ＡＴＰ的生物效应。依结构特征激活剂分８大类，对于研制新型抗心绞痛、抗心肌梗死和抗高血压药物开辟了一个新方向。以格列本脲为代表的硫脲类药物是ＫＡＴＰ选择性拮抗剂，其作用环节可能是作用于硫脲受体后才发挥拮抗效应的，硫脲受体隶属ＡＴＰ结合蛋白家族，其生理学作用已形成又一个研究热点
Cardiovascular ATP-sensitive potassium channels (KATP) are an inward rectifier potassium channel regulated by intracellular ATP concentrations. In the physiological state, in the closed state; hypoxic pathological state, play an important regulatory role. Cardiovascular KATP has a high selectivity for potassium ion permeability. Its single-channel conductance in heart and vascular smooth muscle is 80 and 135 pS, respectively. The channels are open and clustered and separated by a long-term blockage. KATP functional structures include channel gates, transitional subunits, ATP binding inhibitory subunits, phosphorylation sites and nucleoside diphosphate binding sites. ATP has a bidirectional regulatory effect on KATP function: Ligand function refers to the binding of ATP binding inhibition subunit, which closes the channel; and the hydrolysis-dependent effect refers to the phosphorylation of the conversion subunit by ATP in the presence of Mg2 + and the opening of the channel. Nucleoside diphosphate binds to its specific site, not only reduces the channel sensitivity to ATP, but also directly leads to the opening of the channel. Depending on the role of KATP activators into three categories, its pharmacological effects depend on the functional status of the channel, in particular, phosphorylation sites, nucleoside diphosphate binding sites and biological effects of ATP. According to the structural characteristics of activator points 8 categories, for the development of new anti-angina, anti-myocardial infarction and anti-hypertensive drugs has opened up a new direction. Thiourea, represented by glyburide, is a selective antagonist of KATP, and its action may play an antagonistic effect after acting on the thiourea receptor. The thiourea receptor belongs to the ATP binding protein family, and its physiological role Has formed another research hot spot