大鼠股骨骨折后肾髓质浅层细胞的凋亡及三七总皂苷的保护作用

摘要

目的：研究三七总皂苷(PNS)对大鼠股骨骨折后肾髓质浅层细胞凋亡的影响及其对骨折后肾损伤的保护作用。方法将102只 Wistar 大鼠随机分为单纯骨折组(36只)、骨折治疗组(36只)、正常对照组(30只)；前两组大鼠分别在骨折建模后1、6、12、24、36、48 h 时各处死6只,在相同时间段正常对照组处死5只。HE 染色观察肾髓质的病理变化,TUNEL 染色观察凋亡细胞,免疫组化及原位杂交技术检测 Bcl-2和 Bax 在肾髓质浅层组织中的表达。结果单纯骨折组中位于肾髓质浅层的肾小管上皮细胞可见轻度颗粒变性,间质小血管轻度扩张淤血；骨折治疗组与单纯骨折组相比,病变程度较轻。在单纯骨折组中,Bcl-2及 Bcl-2 mRNA 表达在1~36 h 明显高于正常对照组(P <0.01)；Bax 表达在12~36 h 较正常对照组高(P <0.01),Bax mRNA 表达自骨折6 h 以后开始高于正常对照组(P <0.01)。在骨折治疗组,Bcl-2表达在1 h 明显比单纯骨折组高(P <0.01),Bcl-2 mRNA 表达在1~48 h 均高于单纯骨折组(P <0.01)；Bax 及 Bax mRNA 表达在1~48 h 均较单纯骨折组低(P <0.01)。结论骨折创伤对肾髓质浅层 Bcl-2、Bax 蛋白的表达及 mRNA 的转录均有明显影响。PNS 可能通过上调抑凋亡基因 Bcl-2以及下调促凋亡基因 Bax 的表达,从而起到抑制组织细胞凋亡的作用。%Objective To study the effects of panax notoginseng saponins (PNS)on rat superficial renal medulla cells after femoral fracture and to discuss the protective role of PNS in renal injury after fracture. Methods We divided 102 Wistar rats randomly into simple fracture group (n =36),fracture and medication group (n =36)and normal control group (n =30).In the former two groups 6 rats were respectively executed at 1,6,12, 24,36,48 h after fracture modeling,while 5 rats in normal control group were executed at the corresponding time points.Regular HE staining was used to observe pathological changes and TUNEL was used for apoptotic cells.And immunohistochemistry and in situ hybridization were used to detect the expressions of Bcl-2 and Bax in superficial renal medulla tissues.Results In simple fracture group,mild granular degeneration could be seen in renal tubular epithelial cells of superficial renal medulla and the interstitial small vessels were slightly expanded and congested. Compared with simple fracture group,the lesions were slighter in fracture and medication group.In simple fracture group,Bcl-2 and Bcl-2 mRNA expressions were significantly higher than those in normal control group at 1 -36 h (P <0.01).Bax expression was higher than that in normal control group at 12-36 h (P <0.01),and Bax mRNA expression was higher than that in normal control group after 6 h after fracture (P < 0.01 ).In fracture and medication group,Bcl-2 expression was obviously higher than that in simple fracture group at 1 h (P <0.01),and Bcl-2 mRNA expression was higher than that in simple fracture group at 1 -48 h (P <0.01).Bax and Bax mRNA expressions were both lower than those in simple fracture group at 1 - 48 h (P < 0.01 ).Conclusion Fracture trauma has significant influences on protein expression and mRNA transcription of Bcl-2 and Bax in superficial renal medulla.PNS can upregulate anti-apoptosis gene Bcl-2 and downregulate pro-apoptosis gene Bax,thus playing the role of inhibiting tissue cell apoptosis.