星形胶质细胞活化后瞬时受体电位通道6在TBI中的作用

目的 探讨大鼠颅脑损伤(TBI)后星形胶质细胞(AST)瞬时受体电位通道(TRPC)6在TBI中扮演的角色.方法 将健康成年雄性SD大鼠39只分为假手术组、致伤组和去铁胺(DFX)组,每组13只.参照Feeney法建立大鼠大脑冲击伤模型,完成Morris水迷宫实验、大脑缺损体积,免疫荧光检测TRPC6与神经胶质原纤维酸性蛋白质(GFAP)共表达,以及Western blot定量检测TRPC6水平.结果 DFX组比致伤组大鼠大脑缺损体积明显减小[(115.35±13.70)mm3 vs.(209.99±16.70)mm3,P＜0.05],Morris水迷宫实验发现DFX组平台搜索策略[(3.13±0.35)分]和搜索时间[(36.15±26.63)s]均较致伤组[(2.13±0.64)分和(110±47.34)s]明显改善(P＜0.05).免疫荧光双标发现DFX组GFAP高表达,且与TRPC6共表达增多.Western blot定量检测发现DFX组TRPC6明显下调(P＜0.01).结论 大鼠TBI早期DFX治疗后AST活化,TRPC6高表达,进而起到神经保护作用.

Effect of TRPC6 after astrocytes activation in traumatic brain injury

Objective To explore the role of astrocytes transient receptor potential channel 6(TRPC6) in rat brain injury (TBI).Methods Thirty-nine male Sprague-Dawley(SD) rats were divided into the sham operation group,injury group and deferoxamine(DFX) group(n=13).According to the previous model construction scheme established by our research group Feeney method,the rat brain impact injury model was established.The Morris water maze test was performed and the defected brain volume was measured.The immunofluorescence was adopted to detect the co-expression of TRPC6 and GFAP.Then Western blot was performed.Results The defected brain volume after TBI in the DFX group was significantly decreased compared with the injury group [(115.35 ± 13.70)mm3 vs.(209.99 ± 16.70)mm3]] (P＜0.05).The Morris water maze test found that the platform search strategy and search time in the DFX group were(3.13 ± 0.35) and(36.15 ± 26.63)s,which were significantly improve d compared with (2.13±0.64) and(110±47.34)s in the injury group(P＜0.05).The immunofluorescence found that GFAP in the DFX group was highly expressed,moreover the co-expression with TRPC6 was increased.Western blot found that TRPC6 in the DFX group was significantly down-regulated(P＜0.01).Conclusion In rat TBI early stage,strocytes are activated after DFX treatment and TRPC6 is highly expressed,playing a neuroprotective role.