丙氨酰—谷氨酰胺二肽对脑外伤大鼠心肌细胞的保护作用

Effect of Alanyl-Glutamine on protection of myocardial cells after traumatic brain injury in rats

目的探讨丙氨酰—谷氨酰胺二肽(Ala-Gln)对创伤性脑损伤(TBI)大鼠心肌细胞的保护作用。方法48只健康雄性Wister大鼠随机分为假手术对照组(A组)、TBI组(B组)和TBI后Ala-Gln干预组(C组)。各组大鼠均于伤后48 h处死取材,测定血清天门冬氨酸转氨酶(AST)和心肌型肌酸激酶同工酶(CK-MB);测定心肌组织超氧化物歧化酶(SOD)和丙二醛(MDA)水平,并观察心肌病理学改变。结果与A组比较,B组大鼠48 h血清AST、CK-MB水平升高,心肌组织SOD减少、MDA增加,同时光镜下可观察到心肌组织水肿变性、炎细胞浸润和灶性坏死等改变;C组心肌细胞变性和坏死明显减轻,血清心肌酶及心肌组织SOD、MDA水平较B组有不同程度改善,并且呈明显的时效关系。结论TBI后可出现心肌损伤,应用Ala-Gln可有效减轻TBI引起的心肌损害,在创伤早期应用效果更显著。

Objective To investigate the effect of Alanyl-Glutamine（Ala-Gln） on protection of myocardial cells after traumatic brain injury（TBI） in rats.Methods Forty-eight healthy male Wistar rats were randomly divided into three groups： control group（group A）,TBI group（group B） and Ala-Gln group（group C）.The serum levels of myocardium-type creatine kinase isoenzyme（CK-MB）,aspartate aminotransferase（AST）,and the myocardium levels of malonaldehyde（MDA）,superoxide dismutaseon（SOD） were measured.The morphologic changes of myocardium were observed with light microscope.Results Compared with group A,the serum levels of CK-MB and AST increased significantly,in group B,the MDA value of myocardium was increased after brain injury,however,the SOD value of myocardium was decreased,which were also significantly different from those in group A.Degeneration and necrosis of myocardium were detected with light microscope in group B,which included increasing and swelling of mitochondria and disruption of cardiac muscle fiber.Serum CK-MB,AST and the MDA,SOD value for the myocardium in group C were alleviated time dependently compared with group B.Relief of myocardial damage was also observed with light microscope in group C.Conclusions TBI can lead to myocardial damage,which may be alleviated by Ala-Gln effectively at earlier stage.