鼠神经生长因子对大鼠创伤性脑损伤合并海水淹溺后脑组织β-APP和NF-L表达的影响

Effects of mNGF on the expressions ofβ-APP and NF-L in rats with traumatic brain injury complicated by seawater drowning

目的观察鼠神经生长因子(mouse nerve growth factor,mNGF)对创伤性脑损伤(traumatic brain injury,TBI)合并海水淹溺(seawater drowning,SWD)大鼠脑组织含水量、海马组织β-淀粉样前体蛋白(β-amyloid precursor protein,β-APP)及神经丝蛋白轻链多肽(neurofilament light polypeptide,NF-L)表达的影响,评估其干预效果。方法60只SD大鼠随机分为假手术(Sham)组(n=12)、TBI+SWD组(n=24)、mNGF组(n=24)。采用Marmarou颅脑致伤法及气管内泵入海水法建立大鼠模型。mNGF组于伤后立即腹腔注射1 ml mNGF(3μg/kg),Sham组、TBI+SWD组腹腔注射等量生理盐水。采用干湿质量法、苏木精-伊红(HE)染色法和免疫组织化学(IHC)染色法分别检测大鼠脑组织含水量及海马组织病理变化、β-APP和NF-L的表达。结果mNGF组与TBI+SWD组脑组织含水量相似,差异无统计学意义(P>0.05);与TBI+SWD组比较,mNGF组海马组织中β-APP及NF-L表达减弱。结论mNGF可减弱β-APP及NF-L表达,对TBI+SWD大鼠神经细胞具有保护作用。

Objective To evaluate the effects of mouse nerve growth factor(mNGF)on the brain water content and the expressions ofβ-amyloid precursor protein(β-APP)and neurofilament light polypeptide(NF-L)in rats with traumatic brain injury(TBI)complicated by seawater drowning(SWD).Methods A total of 60 male rats were randomly divided into three groups:Sham group(n=12),TBI+SWD group(n=24),and mNGF group(n=24).The rat models were created on the basis of Marmarou′s weight-drop TBI modeling and instilling seawater into the trachea by syringe pump.The mNGF group was administered mNGF intraperitoneally;while the Sham group and the TBI+SWD group were injected with an equivalent amount of normal saline.The brain water content was measured by using the dry-wet weight method.The pathological changes of the hippocampal tissue and the expressions ofβ-APP and NF-L were observed through hematoxylin-eosin(HE)staining and immunohistochemical(IHC)staining.Results Brain water content in the mNGF group was similar to that in the TBI+SWD group(P>0.05).Compared with the TBI+SWD group,the expressions ofβ-APP and NF-L in the hippocampal tissue of the mNGF group were significantly reduced.Conclusion mNGF can reduce the expressions ofβ-APP and NF-L,and protect the neurons of the rats after TBI+SWD.