实验性糖尿病大鼠肺组织晚期糖基化终末产物、肺表面活性物质蛋白质A免疫组织化学分析

The immunohistochemical analysis of AGEs, SP-A in the lung of diabetic rats

目的 探讨实验性糖尿病（diabetes mellitus,DM）大鼠肺组织晚期糖基化终末产物（advanced glycosylated endproducts,AGEs）、肺表面活性物质蛋白质A（surfactant proteins A,SP-A）的变化.方法 48只SD雄性大鼠随机分为DM组和对照组,每组24只.链脲佐菌素（streptozotocin,STZ）60mg/kg尾静脉注射制造DM模型.分别于造模成功后4、12、20周末杀检.免疫组织化学方法 观察肺组织AGEs、SP-A的变化,并进行图像分析（灰度值以0为黑,最大值为白）.结果 （1）AGEs：DM大鼠肺泡上皮细胞、支气管黏膜上皮细胞、血管内皮细胞及平滑肌细胞可见大量AGEs阳性细胞,平均灰度值低于对照组（4周93.92±7.92 vs 104.75±8.20;12周76.25±6.76 vs 93.50±7.56;20周47.63±7.96 vs 142.38±19.76;P均＜0.05）,随着DM病程的增加逐渐降低.（2）SP-A：4周DM大鼠肺泡Ⅱ型细胞、肺泡巨噬细胞、克拉拉细胞可见少量阳性细胞,12、20周可见大量SP-A阳性细胞,平均灰度值均低于对照组（12周75.63±6.70 vs 110.50±13.20;20周47.38±4.84 vs 97.25±9.87;P均＜0.01）.结论 DM大鼠随着病程的增加,出现肺泡Ⅱ型细胞的损伤,可能与AGEs的沉积有关.

Objective To approach the changes of advanced glycosylated end products （AGEs）, surfactant proteins A（SP-A） in the lung of experimental diabetic rats and their relationship. Methods 48 male SD rats were divided into diabetes mellitus （DM） group and control group, each group with 24 rats. The DM rat model was made by injecting streptozocin （60mg/kg） into caudal vein. The rats were killed and the lung was individually taken out at the end of 4, 12 and 20 weeks after the models were established. The changes of AGEs, SP-A in rats lung were observed with imrnunohistochemical assay and the images were analyzed（ black is minimum of gray, white is maximum of gray）. Results We observed a great quantity of AGEs positive cells in the alveolar epithelial cells, bronchial mucosal epithelium, angio-endothelial celland smooth muscle cells of the DM rats. The average gray （AG） was inferior to that of the controls （4weeks 93.92±7.92 vs 104.75 ±8.20;12 weeks 76.25 ±6.76 vs 93.50 ±7.56;20 weeks 47.63 ±7.96 vs 142. 38 ± 19. 76; P 〈0. 05） and decreased with the DM course. In the 4 weeks DM rats, there were a few SP-A positive cells in the type I/ alveolar epithelial cells, Clara cells and alveolar macrophage cells. In the 12 and 20 weeks DM rats, there were a great many CTGF and TGF-131 positive ceils. The AG was inferior to that of the controls（ 12 weeks 75.63 ± 6.70 vs 110. 50 ± 13.20;20 weeks 47.38 ± 4. 84 vs 97.25 ± 9. 87 ; P 〈 0. 01 ）. Conclusion With the progress of diabetes, DM rats＇ pulmonary alveolar type II cells injury appeared, that might be related with the deposition of AGEs.