烟雾吸入伤大鼠肺组织85_(KD)磷脂酶A_(2)变化初探

Parimary study on the change of 85_(KD) phospholipase A_2 in lung tissue of rats with smoke inhalation injury

目的 探讨 85 KD磷脂酶A2 (85 KDPLA2 )在烟雾吸入伤大鼠肺组织中的表达与活性变化及其变化的可能机制。方法 85 KDPLA2 酶表达相对含量用酶联免疫吸附法测定 ;85 KDPLA2 活性用生化法测定。同时检测肺混合细胞浆钙浓度和肺匀浆髓过氧化物酶 (MPO)活性。结果 烟雾吸入伤后 ,肺匀浆 85 KDPLA2 OD值从伤后 1～ 2 4h均高于正常对照组、肺匀浆 85 KDPLA2 活性变化与OD值变化相似 ,而混合细胞胞浆钙浓度和MPO活性分别从伤后 1h和 3h明显高于正常对照组 ,并持续到伤后 2 4h(P <0 .0 5 )。结论 肺组织 85 KDPLA2 酶蛋白表达 ,特别是活性增加可能是烟雾吸入伤后磷脂酶A2 激活的重要原因之一 ,肺实质细胞与中性粒细胞可能是 85 KDPLA2 产生的重要来源 ,而胞浆钙浓度增加可能参与了 85 KDPLA2 的激活过程。

Objective The changes of the enzymatic protein expression and the activity of 85 KD phospholipase A 2(85 KD PLA 2) in lung tissue and it's mechanism were studied on rat's model with smoke inhalation injury.Methods The expression of 85 KD PLA 2 enzymatic protein was detected with enzyme-linked immunosorbent assay(ELISA),the activities of 85 KD PLA 2 in pulmonary homogennate were assayed by biochemistry, and the concentration of cytosolic calcium([Ca 2+ ]) of mixing pulmonary cells and the activity of myeloperoxidase(MPO) in pulmonary homogenate were measured simutaneously.Results There was an increase in the value of OD presenting 85 KD PLA 2 enzymatic protein from 1h to 24h after smoke inhalation injury,the changes of 85 KD PLA 2 activities in pulmonary homogenate resembled the change of OD value, and the concentration of [Ca 2+ ] of mixing pulmonary cells and the activity of MPO in pulmonary homogenate were significantly increased respectively at 1h and 3h and lasted to 24h following smoke inhalation injury comparing with control group(P<0.01). Conclusion The enzymatic protein expression and especially the increase in the activity of 85 KD PLA 2 might be one of important factors of phospholipase A 2 activation after smoke inhalation, pulmonary parenchymal cells and neutripils might be the primal resource of 85 KD PLA 2 generation and the increase in cytosolic calcium might involve in the activation of 85 KD PLA 2.