高糖对人大血管细胞钾依赖钠钙交换蛋白6表达的影响

目的 观察钾依赖钠钙交换蛋白6（NCKX6）基因在人主动脉内皮细胞、平滑肌细胞和巨噬细胞的表达，以及高糖对大血管NCKX6表达的影响。方法 Western印迹检测正常血管组织和2型糖尿病血管组织NCKX6蛋白的差异表达，RT—PCR检测NCKX6基因在人主动脉平滑肌细胞（HASMC）、人主动脉内皮细胞（HAEC）和人血管巨噬细胞（THP-1）中的表达，Northern印迹杂交检测高糖作用HAEC细胞NCKX6mRNA的表达差异。结果 Western印迹初步显示NCKX6在2例糖尿病患者大血管中明显高表达，RT—PCR观察到NCKX6基因主要在HAEC细胞中表达，而HAMSC和THP-1细胞中表达量低。Northern印迹杂交进一步观察到随着培养液D-葡萄糖浓度的增加，作用72h后HAEC细胞NCKX6mRNA表达明显增高，30mmol／LD-葡萄糖作用下NCKX6mRNA表达量可增加5—6倍。结论 NCKX6主要在人主动脉内皮细胞中表达，并且受到葡萄糖的调控。提示NCKX6与糖尿病大血管病变有密切的关系。

Effect of high glucose on the expression of NCKX6 in human macrovascular tissue cells

Objective To observe the expression of K~+-dependent Na~+/Ca~ 2+ exchanger 6 (NCKX6) in endothelial cells, smooth muscle cells and macrophage cells of macrovascular tissue, and the effect of high glucose on the expression of macrovascular NCKX6 mRNA. Methods The protein expression of NCKX6 was analyzed in the normal and diabetic macrovascular tissues by Western blotting. The gene expression of NCKX6 was detected in the human aortal endothelial cells (HAEC)and human aortal smooth muscle cells (HAMSC) and human macrophage cells (THP-1) using RT-PCR. The effect of high glucose on the expression NCKX6 mRNA in HAEC was further observed by Northern blotting. Results The protein expression of NCKX6 was significantly increased in the aorta of 2 patients with diabetes compared with normal subjects. The gene of NCKX6 was predominantly expressed in HAEC , while the expression of NCKX6 was very low in HAMSC and THP-1. With the increase of D-glucose concentration in the culture medium, the level of NCKX6 mRNA was gradually up-regulated 72 h after incubation, with 5 to 6 fold increase at the concentration of 30mmol/L D-glucose. Conclusion NCKX6 is predominantly expressed in HAEC, and its expression is regulated by glucose. NCKX6 tightly correlates with the pathogenesis of diabetic macrovasular complications.