目的:检测弥漫性脑创伤(DBI)大鼠脑内葡萄糖转运体1(GLUT1)和葡萄糖转运体3(GLUT3)的表达以及牛磺酸对其的影响.方法:SD雄性大鼠随机分为假手术组、脑创伤组、低剂量牛磺酸组(200 mg/kg)和高剂量牛磺酸组(300 mg/kg),连续灌胃给药7 d.建立大鼠DBI模型,脑创伤后24 h,免疫组化和Western blotting检测脑组织中GLUT1和GIUT3蛋白的表达;透射电镜观察大脑皮层神经元超微结构的变化.结果:各组脑组织中均可见有GLUT1表达的阳性细胞,其表现为在微血管内皮细胞胞浆或胞膜呈棕黄色.与假手术组相比,脑创伤组大鼠脑GLUT1蛋白表达无显著差异;与脑创伤组相比,低、高剂量牛磺酸组脑GLUT1蛋白表达显著增多(P<0.01);且低剂量牛磺酸组脑GLUT1蛋白表达显著高于高剂量牛磺酸组(P<0.05).各组仅在第三脑室周围可见GLUT3表达的阳性神经元,阳性细胞胞浆或胞膜呈棕黄色.与假手术组相比,脑创伤组大鼠脑GLUT3蛋白表达显著增多(P<0.01);与脑创伤组相比,低、高剂量牛磺酸组脑GLUT3蛋白表达显著增多(P<0.01);且高剂量牛磺酸组脑GLUT3蛋白表达显著高于低剂量牛磺酸组(P<0.01).低剂量牛磺酸组大脑皮层神经元病理改变明显减轻.结论:牛磺酸可对DBI大鼠发挥脑保护作用,其机制可能是上调GLUT1和GLUT3蛋白表达,维持脑组织的能量供给.%AIM: To investigate the effect of taurine on the expression of glucose transporter 1 ( GLUT1 ) and transporter 3 ( GLUT3 ) in rat brain with diffused brain injury ( DBI ).METHODS: Sixty - four male Sprague - Dawley rats were randomly divided into 4 groups: sham - operated group, DBI group, low - dose taurine group ( 200 mg/kg, ig ) and high - dose taurine group ( 300 mg/kg, ig ).After fed with the corresponding drugs for 7 days, the animal model of DBI was made, and the rats were executed 24 h after DBI.The expression of GLUT1 and GLUT3 in the brain was detected by the methods of immunohistochemistry and Western blotting.The pathomorphological changes of the cerebral cortex were observed under electron microscope.RESULTS: The expression of GLUT1 was detected in capillary vascular endothelial cells in each group, and cytoplasm - positive cells or the cells with buffy membrane were observed.No significant difference of the GLUT1 expression in brain tissues between DBI group and sham - operated group was detected.Compared with DBI group, the expression of GLUT1 in the brain tissues were significantly increased in low - and high - dose taurine groups ( P ＜0.01 ).The expression of GLUT1 in the brain tissues in low - dose taurine group were significantly higher than that in high - dose taurine group ( P ＜0.05 ).The positive staining of GLUT3 only appeared in the periphery of the third ventricle in each group in the cells with buffy membrane or positive cytoplasm.The expression of GLUT3 in the brain tissues in DBI group was significantly higher than that in sham - operated group ( P ＜0.01 ).The expression of GLUT3 in the brain tissues in low - and high - dose taurine groups was significantly higher than that in DBI group ( P ＜0.01 ).Compared with low dose taurine group, the expression of GLUT3 in the brain tissues were significantly increased in high - dose taurine group ( P ＜0.01 ).The pathological damage of cerebral cortex in low - dose taurine group was obviously alleviated.CONCLUSION: Taurine may take part in the neuroprotective mechanisms in DBI by increasing the expression of GLUT1 and GLUT3 at protein level to maintain the energy supply in brain tissues.
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