目的　为了提取肺表面活性物质蛋白A ,提高人工合成表面活性物质的疗效。方法　采用萃取和透析的方法提纯肺表面活性物质蛋白A ,并用膜天平检测其生物活性。结果　蛋白质聚丙烯酰胺凝胶电泳显示 ,提纯后的肺表面活性物质蛋白A分子量为 2 9.7× 10 3 ,其杂蛋白条带明显减少 ,将其加入人工合成的磷脂中表现为表面活性明显增加 ,γmin由 7.9± 0 .9降至 2 .6± 1.2。结论　用萃取和透析的方法能较好地提纯肺表面活性物质蛋白A ,且能较好地保持其生物活性。

Objective To improve the isolation effect of the pulmonary surfactant protein A. Methods We isolated and purified pig pulmonary surfactant protein A. The pig lungs were washed with saline. The mixture was centrifugalized and protein sediments were obtained. The sediments were isolated and purified by dialysis. We detected their biological activity by MTP-1 balance. Results The samples upon SDS/polyacrylamide gel electrophoresis showed that the molecular weight was 29.7 ×10 3 and the number of bands was reduced. When added to artificial phospholipids, its biological activity was enhanced ( P < 0.01 ). Conclusions The method of dialysis can effectively purify the pig pulmonary surfactant protein A. The method can also keep its biological activity well.