甲泼尼龙对百草枯中毒大鼠肾脏损伤的保护作用

目的探讨甲泼尼龙对百草枯中毒大鼠肾脏损伤的保护作用及其作用机制。方法将30只健康SD大鼠随机分为百草枯模型组、甲泼尼龙治疗组和对照组，每组各10只。分别在第1、3、7天取各组大鼠舌下静脉血，检测血尿素氮（BUN）和血清肌酐（Cr）水平，在第7天分离各组大鼠肾组织观察病理结果变化，免疫组化SABC法染色，观察肾脏巨噬细胞移动抑制因子（MIF）的表达情况。结果血BUN和血清Cr水平：与对照组比较，百草枯模型组第3、7天水平升高（P〈0．05），与百草枯模型组比较，甲泼尼龙治疗组第3、7天水平降低（P〈0．05）。大鼠肾脏病理改变：与对照组比较，百草枯模型组改变有结构紊乱、变性坏死、炎症细胞浸润、充血水肿等；与百草枯模型组比较，甲泼尼龙治疗组改变显著减轻。肾小管细胞MIF表达：与对照组相比，百草枯模型组MIF表达增多（P〈0．05）；与百草枯模型组相比，甲泼尼龙治疗组MIF表达减少（P〈0．05）。结论甲泼尼龙可能是通过减少MIF表达，抑制炎症反应，从而减轻百草枯对大鼠肾脏的损伤。

Protective effects of methylprednisolone on kidney in rats poisoned by paraquat

Objective To investigate the protective effect and mechanism of methylprednisolone on kidney in the rats poisoned by paraquat. Methods 30 SD rats were randomly divided into three groups, paraquat exposure group, methyl- prednisolone treatment group and control group, with 10 rats in each group. The rats were draw blood from the sublin- gual vein on the 1st, 3rd and 7th day,and then the plasma Cr and BUN level were measured, the rats were sacrificed to observe pathological changes of kidney, and immunohistochemical determination of macrophage emigration inhibito- ry factor （MIF） expression on the 7th day. Results Compared with the control group, the levels of Cr and BUN in- creased obviously in the paraquat exposure group on the 3rd, 7th day （P 〈 0.05）, compared with the paraquat exposure group, the levels of Cr and BUN decreased obviously in the methylprednisolone treatment group on the 3rd, 7th day （P 〈 0.05）. The pathological changes of kidney were congestion and edema, inflammatory cell infiltration, degeneration and necrosis and structural disorder in the paraquat exposure group, while in the methylprednisolone treatment group the changes were slighter. Compared with the control group, MIF-positive cells expression increased in the paraquat exposure group（P 〈 0.05）; compared with the paraquat exposure groups, MIF-positive cells expression decreased in the methylprednisolone treetment group （P 〈 0.05）. Conclusion Methylprednisolonc may protect the kidney of rats poi- soned by paraquat by inhibiting the inflammatory response.