波动性高糖对内皮细胞血管舒张因子合成的影响

The Effects of Intermittent High Glucose on the Production of Vascular Relaxing Factors in Human Umbilical Vein Endothelial Cells in Vitro

目的对比研究波动性与恒定性高糖对血管内皮细胞血管舒张因子合成的影响。方法以体外培养人脐静脉内皮细胞为研究对象,分别测定波动性高浓度葡萄糖(5或20 mmol/L)与恒定性高浓度葡萄糖(20 mmol/L)环境下内皮细胞合成的血管舒张因子前列环素及一氧化氮的含量,同时观察培养液中丙二醛含量的变化。前列环素应用放射免疫法测定其稳定代谢产物,而一氧化氮及丙二醛的检测则分别应用Griess法与Schuh法。结果波动性高糖组前列环素与一氧化氮均明显低于恒定高糖组(分别为21±6 ng/L比36±8 ng/L,P<0.01;13.6±2.0mmol/L比18.2±3.7 mmol/L,P<0.001),而波动性高糖组的丙二醛则明显高于恒定性高糖组(16.5±2.7 mmol/L比13.2±2.2 mmol/L,P<0.05)。结论波动性高血糖较恒定性高血糖对血管内皮细胞可能具有更强的损伤效应。

Aim To compare the effects of intermittent and constant high glucose media on the production of vascular relaxing factors in cultured human umbilical vein endothelial cells （hUVEC）. Methods hUVEC were grown to confluence and were exposed for 7 days to 5 mmol/L glucose （normal control）, 20 mmol/L glucose（constant high glucose） and 5 mmol/L alternating with 20 mmol/L glucose （ intermittent high glucose） on a daily basis.The concentration of 6-keto-PGF1α（the stable hydrolysed product of prostacyclin） was determined by radioimmunoassay, the nitric oxide （NO） was measured by means of Griess reaction and the malondialdehyde （MDA） content was detected by the method described by Schuh. Results Both the 6-Keto- PGF1α and NO in intermittent high glucose group were significandy lower than that in constant high glucose group （21±6 ng/L vs 36±8 ng/L, P〈0.01 ; 13.6±2.0 mmol/L vs 18.2±3.7 mmol/L, P〈0. 001 respectively ）. However, the intermittent glucose group had increased MDA （ 16.5±2.7 mmol/L vs 13.2±2.2 mmol/L, P〈0.05 ） compared with constant glucose group. Conclusion These findings suggest that variability in glycemic control could be more deleterious to endothelial cells.