重组人脑钠尿肽干预大鼠心肌细胞缺氧／复氧对葡萄糖转运的机制研究

Mechanism study of glucose transport by recombinant human brain natriuretic peptide pretreating myocardial cells in rats with hypoxia/reoxygenation

目的探讨重组人脑钠尿肽（rh-BNP）体外干预大鼠心肌细胞缺氧／复氧模型对葡萄糖转运子（GLUT1／GLUT4）分布及表达的影响。方法原代培养6～8周健康成年SD大鼠的左心室心肌细胞，将培养的细胞分成5组，即正常对照组、缺氧培养组、缺氧／复氧组、rh-BNP干预缺氧组、rh-BNP干预缺氧／复氧组。MTT检测各组细胞活力的变化，ELISA检测各组细胞乳酸脱氢酶（LDH）、谷胱甘肽、超氧化物歧化酶（SOD）和脑钠尿肽（BNP）水平，RT-PCR检测各组细胞诱导型一氧化氮合酶（iNOS）、内皮细胞型一氧化氮合酶（eNOS）、GLUTI、GLUT4的mRNA表达水平。结果rh-BNP干预处理使缺氧和缺氧／复氧心肌细胞活力显著上升，差异有统计学意义（P〈0．05），并降低了缺氧和缺氧／复氧细胞中LDH、谷胱甘肽、SOD和BNP的水平，差异有统计学意义（P〈0．05）；提高了心肌细胞中iNOS、eNOS、GLUTl、GLUT4的mRNA表达。结论rh-BNP干预缺氧／复氧的大鼠心肌细胞可能通过影响细胞内的氧化应激水平以及GLUT0、GLUT4的表达，进而减轻心肌损伤。

Objective To investigate the mechanism of glucose transport by recombinant human brain natriuretic peptide（rh-BNP） pretreating myocardial cells in rats with hypoxia/reoxygenation. Methotis Left ventricular cardiomyocytes were obtained from SD rats aged 6 - 8 weeks and were cultured in vitro. They were divided randomly into 5 groups including the control group, hypoxia group, hypoxia/reoxy- genation group, rh-BNP pretreating hypoxia group and rh-BNP pretreating hypoxia/reoxygenation group. MTT assay was used to detect the changes of cells viability. The levels of lactate dehydrogenase （ LDH）, glutathione, superoxide dismutase （SOD） and BNP were measured by ELISA. The expression of iNOS, eNOS, GLUT1 and GLUT4 were detected by RT-PCR. Results The rh-BNP intervention significantly increased the viability of hypoxia and hypoxia/reoxygenation treated cardiomyocytes （P 〈 0. 05 ） , reduced the levels of LDH, glutathione, SOD and BNP induced by hypoxia and hypoxia/reoxygenation（ P 〈 0. 05 ）, and increased the mRNA expression of iNOS, eNOS, GLUT1 and GLUT4 in cardiomyocytes （P 〈 0. 05 ）. Conclusion The rh-BNP alleviates hypoxia/reoxygenation-induced cardiomyoeytes injury by affecting oxidative stress and the expression of GLUT1 and GLUT4. [ Key words ] Recombinant human brain natfiuretic peptide; Hypoxia/Reoxygenation; Glucose transporter ; Oxidative stress