早期糖尿病大鼠模型玻璃体VEGF及其受体sFlt-1、KDR的研究

目的观察早期糖尿病大鼠玻璃体血管内皮生长因子(vascular endothelial growth factor,VEGF)、血管内皮生长因子可溶性fm样酪氨酸激酶受体1(soluble fms-like tyrosine kianse-1,sFlt-1)及VEGF受体2(kinase insert domain-containing receptor,KDR)的变化,探讨各生长因子浓度变化与早期糖尿病视网膜病变的关系。方法 40只成年雄性SD大鼠随机分为两组。模型组30只,使用链脲佐菌素(streptozotocin,STZ)腹腔注射法诱发糖尿病,对照组10只腹腔注射生理盐水。72h后使用德国拜安易(拜耳集团)血糖仪检测血糖,血糖≥16.67mmol·L-1为造模成功,血糖未达标者再次注射STZ造模。造模当天及建模后1周、2周、4周连续测量大鼠测血糖;造模当天及建模后1周、4周测体质量;4周时取大鼠玻璃体,ELISA检测VEGF、sFlt-1、KDR的含量,多聚甲醛固定眼球并石蜡包埋行HE染色。结果 STZ腹腔注射糖尿病大鼠成模率100%,1个月后死亡率为30%。模型组存活21只,对照组10只。1周、2周、4周时模型组与对照组血糖浓度差异均有统计学意义(均为P<0.05),前者均低于后者;1周时两组体质量差异无统计学意义(P=0.279),4周时模型组体质量(240.00±27.43)g与对照组(318.50±41.37)g差异有统计学意义(P=0.000)。视网膜HE染色显示模型组较对照组细胞肿胀,组织排列紊乱。ELISA检测模型组、对照组VEGF含量分别为(0.2690±0.2205)ng·mL-1、(0.2499±0.0206)ng·mL-1;sFlt-1含量分别为(5.9020±0.6133)ng·mL-1、(6.1742±0.4912)ng·mL-1;KDR含量分别为(2.7783±0.2924)ng·mL-1、(2.5024±0.3326)ng·mL-1。模型组大鼠玻璃体VEGF与KDR均较对照组升高,两组差异均具有统计学意义(P=0.036、0.033)。模型组sFlt-1含量较对照组降低,但差异无统计学意义(P=0.244)。结论大鼠早期糖尿病模型玻璃体中VEGF和KDR之间的浓度变化,与糖尿病所致早期视网膜病变有关。

Research on VEGF,sFlt-1 and KDR in vitreous of early diabetic rats

Objective To determine the vitreous level of soluble vascular endothelial growth factor receptor-1(SFlt-1),vascular endothelial growth factor(VEGF) and kinase insert domain-containing receptor(KDR) in early diabetic rats,and discuss the role of sFlt-1,VEGF and KDR in early diabetic retinopathy.Methods Forty adult male SD rats were randomly divided into two groups,30 rats in model group were injected intraperitoneally with streptozotocin to induce diabetes,and 10 rats in control group were injected with normal saline.Blood glucose meter was used to detect the blood glucose level at 72 hours after injection,and the level higher than or equal to 16.67 mmol·L-1 was considered to be the successful standard for modeling,if the level did not reach the standard,the streptozotocin was injected again.The blood glucose was examined by electronic scale at the same day,1 week,2 weeks and 4 weeks after modeling,the body mass was measured at the same day,1 week,and 4 weeks after modeling.At 4 weeks after modeling,the vitreous were collected,and the VEGF,sFlt-1 and KDR levels were detected by ELISA.Meanwhile,the eye balls were fixed in paraform and embedded by petrolin for HE staining.Results The successful modeling rate was 100%,and the mortality rate after 1 month was 30%,21 rats survived in model group while 10 in control group.The blood glucose at 1 week,2 weeks and 4 weeks between model group and control group had statistical differences(all P<0.05),the former were lower than the latter.The weight at 1 week between two groups had no difference(P=0.279),but there was statistical difference at 4 weeks between model group(240.00±27.43)g and control group(381.50±41.37)g(P=0.000).The HE staining analysis showed that the cells in model group were more tumid that that in control group and the tissue arranged irregularly.The ELISA results showed that the VEGF level in model group and control group were(0.269 0±0.220 5)ng·mL-1 and(0.249 9±0.020 6)ng·mL-1,sFlt-1 level were(5.902 0±0.613 3)ng·mL-1 and(6.174 2±0.491 2)ng·mL-1,KDR level were(2.778 3±0.292 4)ng·mL-1 and(2.502 4±0.332 6)ng·mL-1,respectively.At the early stage of diabetic retinopathy,the VEGF,KDR level in model group were higher than that in control group(P=0.036,0.033),and the sFlt-1 level in model group was lower than that in control group,but there was no statistical difference(P=0.244).Conclusion The changes of VEGF and KDR level in vitreous of early diabetic rats are related to the early retinopathy induced by diabetic.