血小板活化因子对肾小球系膜细胞合成前列腺素E_2的影响

EFFECTS AND SIGNIFICANCE OF PLATELET ACTIVATING FACTOR ON THE PROSTAGLANDIN E2 IN RAT GLOMERULAR MESANGIAL CELLS

目的 :探讨血小板活化因子 (PAF)对肾小球系膜细胞 (GMC)合成前列腺素E2 (PGE2 )的影响及其意义。 方法 :测定PAF刺激对GMC合成PGE2 的影响。 结果 :PAF刺激GMC显著增加PGE2 的合成并呈剂量依赖性。 10 -5mol/LPAF在 5min内即刺激GMC合成PGE2 显著增加。刺激PGE2 合成的PAF阈值为 10 10mol/L ,刺激半量和最大量PGE2 合成的PAF浓度分别约为 10 -8mol/L和 10 -7mol/L。溶PAF无刺激GMC合成PGE2 作用。PAF受体拮抗剂BN5 2 0 2 1能抑制PAF刺激GMC合成PGE2 。PGE2 对肾小球功能有保护作用。 结论 :PAF介导肾小球肾炎发病中的作用 ,能由其诱导PGE2

OBJECTIVE To explore the effect and significance of platelet activating factor(PAF) on prostaglandin E2(PGE2) synthesis in rat glomerular mesangial cell (GMC) in culture. METHODOLOGY The PGE2 synthesis in cultured rat GMC was measured with RIA. A range of different concentrations of PAF(10 5 ～10 -10 mmol/L) were used to stimulate the synthesis of PGE2 in cultured GMCs. A PAF receptor antagonist, BN52021,was used to examine the effect of PAF on the PGE2 synthesis in GMC. RESULTS PAF significantly stimulated PGE2 synthesis in a dose dependent manner.PAF(10 -8 mol/L) rapidly increased PGE2 synthesis within 5 minutes(10 15fold). Stimulation was observed at 10 10 mol/L PAF, and half maximum and maximum at 10 8 and 10 7 mol/L, respectively. Lyso PAF had no significant effect on PGE2 synthesis. The effect of BN52021 was examined with a constant concentration of 10 7 mol/L PAF. At equimolar concentrations there was no consistent inhibition of PAN stimulated PGE2 synthesis. Significant inhibition(about 60%) was observed at 10 8 mol/L, and maximum inhibition(about 90%) at 10 5 mol/L. CONCLUSION PGE2 is important in maintaining glomerular function during glomerulonephritis.The PGE2 synthesis induced by PAF may counteract the inflammatory effect of PAF in the pathogenesis of glomerulonephritis.