胰岛素和葡萄糖对缺氧血管内皮细胞分泌tPA和PAI-1抗原的影响

目的: 观察胰岛素和葡萄糖对缺氧血管内皮细胞分泌组织型纤溶酶原激活物(tPA)及其抑制物-1(PAI-1)的影响。 方法:培养人脐静脉内皮细胞株ECV-304。分组实验:(1)常氧组;(2)在缺氧条件下又分为Ⅰ:缺氧对照组;Ⅱ:低浓度组:胰岛素150 mU/L、葡萄糖5.5 mmol/L;Ⅲ:中浓度组:胰岛素450 mU/L、葡萄糖15 mmol/L;Ⅳ:高浓度组:胰岛素900 mU/L、葡萄糖30 mmol/L;Ⅴ:渗透压对照组:甘露醇24.5 mmol/L。取培养4、8、12 h 3个时点,用ELISA法测定细胞培养上清液tPA、PAI-1抗原。结果:缺氧明显增加tPA和PAI-1抗原分泌,tPA/PAI-1值明显增加(P＜0.01)。胰岛素和葡萄糖能够刺激缺氧内皮细胞分泌tPA和PAI-1抗原,在缺氧8 h以内,tPA/PAI-1比值明显增加(P＜0.05)。随缺氧时间的延长,tPA/PAI-1值逐渐下降。结论:胰岛素和葡萄糖能够刺激内皮细胞分泌tPA和PAI-1抗原,在缺氧8 h以内,tPA/PAI-1值升高,纤溶活性升高,有利于局部自发性纤溶的发生。此作用可能是IGK治疗急性心肌梗死的机制之一。

Effects of insulin and glucose on secretion of tissue-type plasminogen activator and its inhibitor-1 in hypoxic vascular endothelial cells

AIM: To study the effects of insulin and glucose on tissue-type plamingen activator (tPA) and its inhibitor-1 (PAI-1) secretion in cultured human endothelial cells. METHODS: Human endothelial cell line ECV-304 was cultured with glucose and/or insulin at different concentrations with or without hypoxic exposure. RESULTS: The tPA, PAI-1 secretion and ratio of tPA/PAI-1 increased in endothelial cells during hypoxia. Insulin and glucose increased the tPA and PAI-1 secretion in endothelial cells exposed to hypoxia, and increase in tPA/PAI-1 ratio was also observed at 4 h and 8 h. CONCLUSION: Hypoxia stimulates the release of tPA and PAI-1. Insulin and glucose also stimulate the tPA and PAI-1 secretion during hypoxia.