恒定性及波动性高糖对牛视网膜周细胞凋亡的影响

目的探讨恒定性高糖及不同频率的波动性高糖对原代培养的牛视网膜周细胞增生、细胞周期及凋亡的影响。方法以体外培养3代近融合的牛视网膜毛细血管周细胞为对象，分别在对照组（5．5mmol／L）、恒定性高糖组（25mmol／L）及不同波动频率的高糖组（5．5mmol／L与25mmol／L交替，频率分别为6h和24h）中孵育6d，采用MTT比色法观察周细胞增生情况；流式细胞术观察周细胞周期情况；TUNEL法检测培养后周细胞的凋亡率。结果周细胞增生受抑制，周期阻滞，出现典型的细胞凋亡特征。恒定性高糖组的作用高于波动性高糖组（P〈0．05）；波动性高糖组内波动频率越高作用越明显（P〈0．05）。结论恒定性高糖较波动性高糖可能具有更强的抑制周细胞增生、周期阻滞及诱导凋亡作用，波动组间波动频率高者比频率低者作用更明显。

Effect of constant and intermittent high glucose on apoptosis of cultured bovine retinal capillary pericytes

Objective The apoptosis of preicytes is the earliest hallmark in diabetic retinopathy.It is reported that the chronic high glucose in diabetes could induced apoptosis of preicytes,but the influence of intermittent high glucose remain unclear.The study was undertaken to study the effects of constant and intermittent high glucose on the proliferation,apoptosis and cell cycle of preliminary cultured bovine retinal capillary pericytes(BRPs).MethodsBRPs were cultured for 6 days under constant high glucose(25mmol/L)or intermittent high glucose at the concentration of 5.5 /25mmol/L or glucose concentration of 5.5 mmol/L condition(control group),respectively.The proliferation of BRPs was assayed with MTT assay.The cell cycles of BRPs were analyzed by flow cytometry.The apoptosis of BRPs was studied by in situ TUNEL method.ResultsThe proliferation of BRPs was inhibited in high glucose culture group.The inhibiting rate of high concentration of glucose on proliferation of cell was gradually reduced from constant group to intermittent group.The cell cycle was blocked in high glucose culture group,and BRPs showed a typical change of apoptosis.The changes were dominant in the constant high glucose compared with the intermittent high glucose(P<0.05),and the group with a bigger fluctuation frequency might contribute to stronger apoptosis changes(P <0.05).ConclusionThe constant high glucose has a stronger inhibiting action on proliferation of BRPs and inducing apoptosis than intermittent high glucose.