二甲胺四环素对大鼠脊髓损伤后caspase-3、p53表达的影响

目的探讨大鼠脊髓损伤后应用二甲胺四环素（minocycline）对caspase-3、053表达及细胞凋亡的影响。方法成年大鼠随机分为脊髓损伤后应用二甲胺四环素的治疗组（A组）和应用生理盐水对照组（B组），损伤后不同时间点（4h、8h、1d、3d、7d、14d、21d）取材，用HE染色观察损伤脊髓组织病理变化，免疫组化染色检测caspase-3、053表达阳性细胞，原位末端标记法（TUNEL法）标记凋亡细胞，及荧光酶联测定法测定caspase-3的活性。结果HE染色镜检发现脊髓组织病理学改变A组明显轻于B组。A、B两组均发现凋亡细胞及caspase-3、053表达，神经细胞凋亡指数及caspase-3、053表达均为B组〉A组（P〈0．05）。结论二甲胺四环素能抑制大鼠脊髓损伤后caspase-3、053表达及细胞凋亡。

Effect of minocycline on caspase-3, p53 and apoptosis after spinal cord injury in rats

Objective To investigate the effect of minocycline on the expression of caspase-3,p53 and apoptosis after spinal cord injury(SCI)in rats.Methods One hour after spinal cord injury,adult male SD rats were divided randomly to receive 50 mg/kg minocycline intraperitoneally and 24 hour again,followed by 5-day 25 mg/kg minocycline(group A),or normal saline(group B),with 56 rats in each group.After operation,the rats were sacrificed at 4 h,8 h,1 d,3 d,7 d,14 d and 21d(n=4 at each time point),and the injuried spinal tissue specimens were stained with hematoxylin and eosin(HE),immunohistochemistry and terminal deoxynucl-eotidyl transferase-mediated dUTP nick end labeling(TUNEL)method,and caspase-3 activity was examined.Results The histopathologic changes in spinal cord tissues in group B was worse than that in group A.The expression of caspase-3,p53 and apoptotic cells was observed in two groups,and the apoptotic index and the expression of caspase-3,p53 in group B were higher than that in group A(P<0.05).Conclusion Minocycline could inhibit the expression of caspase-3,p53 and apoptosis after SCI in rats.