摘要目的 观察不同浓度乳酸对培养的大鼠视网膜血管内皮生长因子(VEGF)表达的影响.方法 2周龄Sprague-Dawley大鼠36只,根据培养液中乳酸含量分为10、20、30 mmol/L乳酸组,每组均为12只大鼠.处死大鼠,摘出眼球剥离视网膜,将视网膜置入插入式培养皿中培养24 h.培养皿中培养液分别为含10、20、30 mmol/L乳酸的Dulbecco改良Eagle培养液+2%胎牛血清.光学显微镜观察视网膜结构、实时荧光定量聚合酶链反应(RT-PCR)和蛋白质免疫印迹(Western blot)检测VEGF的表达.结果 光学显微镜组织病理学观察结果显示,视网膜层次清晰,结构完整,未见明显细胞溶解和坏死.RT-PCR检测结果显示,10、20、30 mmol/L乳酸组VEGF mRNA表达量分别为0.74±0.06、0.99±0.12、1.45±0.17;Western blot检测结果显示,10、20 mmol/L乳酸组和30 mmol/L乳酸组视网膜VEGF表达量分别为0.34±0.15、0.54±0.16、0.93±0.23.RT-PCT和Western blot检测结果均显示30 mmol/L乳酸组较10 mmol/L乳酸组VEGF表达明显升高.结论 乳酸诱导视网膜VEGF表达有浓度依赖性.

abstractsObjective To investigate if lactic acid can promote the expression of vascular endothelial growth factor (VEGF) in the rat retinal explants. Methods The retinas of two-week neonatal SD rats were placed onto the culture plate inserts and incubated with Dulbecco's modified Eagle's medium (DMEM) plus 2% fetal bovine serum (FBS) containing 10, 20, 30 mmol/L of lactic acid, respectively. Each group had 24 retinas. At 24 hours after incubation, the retinas were sectioned for light microscopy and the expression of VEGF was measured by real time PCR and Western blot. Results The cultured retinas maintained intact construction, and no cytolysis and apoptosis were observed under light microscope. RT-PCR showed the levels of VEGF mRNA were 0.74 ± 0.06 for 10 mmol/L lactic acid group, 0. 99 ± 0. 12 for 20 mmol/L group, and 1.45±0. 17 for 30 mmol/L group respectively. VEGF expression was 0. 34±0. 15 for 10 mmol/L,0. 54±0. 16 for 20 mmol/L, and 0. 93±0. 23 for 30 mmol/L group respectively by Western blot. Both PCR and Western blot showed 30 mmol/L of lactic acid significantly increased the levels of VEGF mRNA and VEGF expression. Conclusion The induction of retinal VEGF by lactic acid is concentration-dependent.