不同温度甘露醇对脑水肿模型小鼠生理指标和脏器结构的影响

Effect of mannitol at different temperatures on physiological indexes and organ structure in model mice with brain edema

目的研究不同温度甘露醇注射液(MT)对脑水肿模型小鼠治疗后生理指标和脏器结构的影响。方法4~6周龄SPF级雄性C57BL/6J小鼠分成5组(每组3~6只):正常对照组(Normal)、脑水肿模型组(LPS)、4℃MT治疗组(4℃MT)、25℃MT治疗组(25℃MT)、37℃MT治疗组(37℃MT)。采用脂多糖(LPS)诱导建立小鼠脑水肿模型,4 h后输注3种不同温度(4℃、25℃、37℃)的20%MT治疗,2 h后用干湿法检测各组小鼠脑组织含水量,取全血检测血常规、血清生化指标[包括丙氨酸氨基转氨酶(ALT)、天冬氨酸氨基转氨酶(AST)、肌酐(Cre)及钾(K^(+))、钠(Na^(+))、氯(Cl^(-))],ELISA检测细胞因子[包括肿瘤坏死因子α(TNF⁃α)、白细胞介素⁃6(IL⁃6)、血管内皮生长因子(VEGF)]水平,取小鼠脑、心、肝、脾、肺、肾进行HE染色,观察脏器病理结构,对比分析3种温度MT对脑水肿模型小鼠治疗效果。结果37℃MT组脑组织含水量显著低于4℃MT组、25℃MT组(P<0.05),接近正常对照组(P=0.2284)。血常规显示,相比于4℃MT组、25℃MT组,37℃MT可有效促进白细胞(WBC)总数回升,维持红细胞(RBC)数量,对血小板(PLT)数量无显著影响。生化分析显示,37℃MT可以显著降低ALT、AST、Cre及K^(+)、Na^(+)、Cl^(-)水平,而4℃MT仅可显著降低ALT,25℃MT仅可降低ALT、AST。ELISA结果显示,37℃MT降低TNF⁃α、IL⁃6分泌,对VEGF无影响;而4℃MT和25℃MT却促进TNF⁃α、IL⁃6的分泌。病理结果显示,37℃MT具有更好减轻脑水肿,心肌纤维水肿,肝、脾、肺、肾淤血及炎症细胞浸润的作用。结论37℃MT治疗脑水肿效果较好,同时可减少炎症反应发生,降低肝、肾功能损伤;4℃MT和25℃MT治疗脑水肿效果欠佳,且存在MT结晶输注引发栓塞、静脉炎等风险。建议MT加温至37℃待结晶消失后应用。

Objective To investigate the effect of mannitol(MT)injection on physiological parameters and organ structure of model mice with brain edema.Methods Male C57BL/6J mice aged 4 to 6 weeks were divided into 5 groups of 3 to 6:normal control(Normal),lipopolysaccharide(LPS),4℃MT(4℃MT),25℃MT(25℃MT),and 37℃MT groups.At 4 h after establishment of a mouse brain edema model by LPS induction and at 2 h after infusion of 20%MT at 3 different temperatures(4℃,25℃,37℃),the water contents of brain tissues in each group were determined using the dry and wet method.Whole blood was collected for blood routine tests and for indicators of serum biochemistry,including levels of alanine aminotransferase(ALT),aspartate aminotransferase(AST),creatinine(Cre)and potassium(K^(+)),sodium(Na^(+))and chloride(Cl^(-)).The levels of cytokines including tumor necrosis factor⁃α(TNF⁃α),interleukin⁃6(IL⁃6),vascular endothelial growth factor(VEGF)were measured by ELISA.The brain,heart,liver,spleen,lung and kidney tissues were used for HE staining to observe the pathological structure of the organs.The effects of three temperatures of MT on mice with brain edema were compared.Results The water content of the brain in the 37℃MT group was significantly lower than that of the 4℃MT group and 25℃MT group(P<0.05),and neared the level of the Normal group(P=0.2284).Blood routine tests showed that compared with the 4℃MT and 25℃MT groups,37℃MT could effectively increase the total number of white blood cells(WBC)and restore the number of red blood cells(RBC),but with no effect on the number of platelets(PLT).Biochemical analysis showed that 37℃MT significantly reduced levels of ALT,AST,Cre and K^(+),Na^(+)and Cl^(-),while 4℃MT significantly reduced ALT alone,and 25℃MT only reduced ALT and AST.ELISA results showed that 37℃MT reduced TNF⁃αand IL⁃6 secretion and had no effect on VEGF,whereas 4℃MT and 25℃MT promoted the secretion of TNF⁃αand IL⁃6.HE staining results showed that 37℃MT could more effectively reduce brain edema,cardiac muscle fiber edema,congestions of the liver,spleen,lung and kidney,and inflammatory cell infiltration.Conclusion 37℃MT has the better therapeutic effect against brain edema while reducing the incidence of inflammatory reactions and mitigating damage to liver and kidney function.The treatment of cerebral edema with 4℃MT and 25℃MT is ineffective,and there is a risk of embolism and phlebitis caused by the infusion of mannitol crystals.It is recommended that MT be used after being heated to 37℃until crystals disappear.