水通道蛋白4在小鼠脂肪栓塞综合征肺损伤模型中的表达及其意义

Changes and significance of aquaporin 4 expression in mice models of fat embolism syndrome

目的 建立脂肪栓塞综合征（fat embolism syndrome,FES）肺损伤动物模型,探讨水通道蛋白4（aquaporin 4,AQP4）在FES肺损伤部分病理过程中的作用. 方法 （1）120只健康成年雄性C57BL/6J小鼠,按随机数表法分为对照组、FES 4 h组、6h组、12 h组、24 h组和48 h组,每组20只.FES组小鼠尾静脉注射同种异体小鼠肾周脂肪,分别在注射脂肪后4,6,12,24,48 h检测小鼠肺组织病理形态、肺湿/干比值（W/D）变化,以确定FES肺损伤模型建立成功并观察其发展过程;采用蛋白质免疫印迹法及免疫组织化学法测定AQP4的表达.（2）36只C57BL/6J小鼠按随机数表法分为对照组、DMSO组、FES 12 h组和AQP4抑制剂组,每组9只.观察抑制AQP4对FES肺损伤病理过程的影响. 结果 （1）与对照组比较,FES组小鼠肺组织损伤明显.W/D值FES 6 h组、12h组、24 h组、48 h组分别为5.06±1.23,5.22±1.58,6.18 ±1.65,5.07 ±0.31,与对照组（3.16±1.58）比较均增加（F=3.62,P＜0.05）.AQP4表达量FES 12 h组、24 h组分别为1.71 ±1.05、1.28±0.68,较对照组0.65±0.08比较均明显增高（F=4.12,P＜0.05）,FES 4 h组0.76 ±0.36、6h组1.17 ±0.60、48 h组0.85±0.45较对照组差异均无统计学意义.（2） FES 12 h组、DMSO组、AQP4抑制剂组W/D值分别为5.22±1.17,4.96±1.66,3.25±1.19,与对照组3.03±1.68比较均明显增高（F=3.69,P＜0.05）;DMSO与FES 12 h组比较差异无统计学意义;AQP4抑制剂与FES 12 h组比较,抑制剂组明显降低. 结论 AQP4可能参与FES肺损伤的部分病理过程,对减轻FES肺损伤起到一定促进作用.

Objective To investigate the role of aquaporin 4 （AQP4） in partial pathologic process of lung injury in rat models of fat embolism syndrome （FES）.Methods A total of 120 healthy male C57BL/6J mice were assigned to control group and FES group which was subgrouped at 4,6,12,24,and 48 hours with 20 mice per group,according to the random number table.Allogeneic perinephric fat was injected to rat caudal veins in FES groups.Lung samples were harvested from each group to examine pathological morphology and lung weight to dry ratio （W/D） to verify the FES models and observe the pathologic process.Expression of AQP4 was detected by western blot and immunohistochemistry.Additional 36 C57BL/6J mice were divided into control group,DMSO group,FES 12-hour group,and AQP4 inhibitor group according to the random number table,with 9 mice per group.Pathologic process of FES-induced lung injury was detected after the inhibition of AQP4.Results Damage to lung tissues was notable in FES group compared with control group.Lung W/D value was 5.06 ± 1.23,5.22 ± 1.58,6.18 ± 1.65,and 5.07 ± 0.31 at 6,12,24,and 48 hours respectively,which was higher than 3.16 ± 1.58 in control group （F =3.62,P 〈 0.05）.Expression of AQP4 was 1.71 ± 1.05 at 12 hours and 1.28 ± 0.68 at 24 hours in FES group,which showed significantly increase when compared with 0.65 ±0.08 in control group （F =4.12,P 〈0.01）,whereas at 4 hours （0.76 ± 0.36）,6 hours （1.17 ± 0.60）,and 48 hours （0.85 ±0.45） in FES group,no statistical difference was observed when compared to control group.W/D value in FES 12-hour group （5.22 ± 1.17）,DMSO group （4.96 ±1.66）,and AQP4 inhibitor group （3.25 ± 1.19） was higher than 3.03 ± 1.68 in control group （F =3.69,P 〈 0.05）.Meanwhile,there was no statistical difference between DMSO and FES 12-hour groups,but significantly lowered W/D value was observed in AQP4 inhibitor group than in FES 12-hour group.Conclusion AQP4 may be implicated in mitigating lung injury induced by FES.