Department of Clinical Medicine, Cardiovascular and Immunologic Sciences, "Federico II" University of Naples, Naples, Italy (G.S., E.C., D.S., C.D.G., A.A., B.T.).
J Am Heart Assoc. 2012 Aug;1(4):e001081. doi: 10.1161/JAHA.112.001081. Epub 2012 Aug 24.
The expression of calcium/calmodulin-dependent kinase IV (CaMKIV) was hitherto thought to be confined to the nervous system. However, a recent genome-wide analysis indicated an association between hypertension and a single-nucleotide polymorphism (rs10491334) of the human CaMKIV gene (CaMK4), which suggests a role for this kinase in the regulation of vascular tone.
To directly assess the role of CaMKIV in hypertension, we characterized the cardiovascular phenotype of CaMK4(-/-) mice. They displayed a typical hypertensive phenotype, including high blood pressure levels, cardiac hypertrophy, vascular and kidney damage, and reduced tolerance to chronic ischemia and myocardial infarction compared with wild-type littermates. Interestingly, in vitro experiments showed the ability of this kinase to activate endothelial nitric oxide synthase. Eventually, in a population study, we found that the rs10491334 variant associates with a reduction in the expression levels of CaMKIV in lymphocytes from hypertensive patients.
Taken together, our results provide evidence that CaMKIV plays a pivotal role in blood pressure regulation through the control of endothelial nitric oxide synthase activity. (J Am Heart Assoc. 2012;1:e001081 doi: 10.1161/JAHA.112.001081.).
钙/钙调蛋白依赖性激酶 IV(CaMKIV)的表达以前被认为仅限于神经系统。然而,最近的全基因组分析表明,高血压与人类 CaMKIV 基因(CaMK4)的单核苷酸多态性(rs10491334)之间存在关联,这表明该激酶在血管张力调节中起作用。
为了直接评估 CaMKIV 在高血压中的作用,我们对 CaMK4(-/-) 小鼠的心血管表型进行了特征分析。与野生型同窝仔相比,它们表现出典型的高血压表型,包括血压升高、心脏肥大、血管和肾脏损伤以及对慢性缺血和心肌梗死的耐受性降低。有趣的是,体外实验表明这种激酶能够激活内皮型一氧化氮合酶。最终,在一项人群研究中,我们发现 rs10491334 变异与高血压患者淋巴细胞中 CaMKIV 表达水平降低有关。
综上所述,我们的研究结果表明,CaMKIV 通过控制内皮型一氧化氮合酶活性在血压调节中起关键作用。