【摘要】 目的研究地塞米松对中性粒细胞凋亡与坏死的调控,阐明地塞米松防治皮瓣缺血-再灌注损伤的机制。方法30只Wistar大鼠腹部制备3cm×6cm岛状皮瓣,分成3组(n=10)。A组:正常皮瓣组;B组:阻断静脉8h,腹腔注射生理盐水作为对照组;C组:阻断静脉8h,腹腔注射地塞米松5mg/kg,作为治疗组。术后7d观察皮瓣成活面积;以AnnexinV及Propidium双标记,流式细胞仪检测全血中性粒细胞凋亡、坏死水平;电镜观察凋亡、坏死中性粒细胞的形态。并于术后1d,从各组大鼠皮瓣中央取材,电镜观察吞噬细胞吞噬凋亡中性粒细胞形态。阻断血管前,再灌注损伤后0、3、6、12及24h,以双夹心ELISA法测量血浆肿瘤坏死因子α(tumornecrosisfactorα,TNF-α)及白细胞介素10(interleukin10,IL-10)浓度。结果皮瓣成活面积A、C组大于B组(P<0.05),A、C组差异无统计学意义(P>0.05)。术后1、3d,B组全血中性粒细胞凋亡含量明显低于A、C组,6d高于A、C组。术后1、3、6d,中性粒细胞坏死水平B组高于A、C组。术后1d,皮瓣中吞噬细胞吞噬凋亡中性粒细胞的数量C组明显高于B组(P<0.05)。B组血浆TNF-α于再灌注1h达到高峰,IL-10于再灌注3h达到最低。C组TNF-α峰值明显低于B组,6h即明显下降;IL-10再灌注1h达最低,3h时明显上升,其浓度明显高于B组。结论地塞米松防治皮瓣缺血再灌注损伤的机制在于调理了中性粒细胞的凋亡水平,减少了中性粒细胞的坏死数量,平衡了中性粒细胞分泌细胞因子。更多还原

【Abstract】 Objective To study the effect of dexamethasone to protect flaps from an ischemia-reperfusion injury and elucidate its mechanism of regulating the death course of the neutrophils. Methods The rats were randomly divided into 3 groups.The vein of the rat was clamped for 8 h after the flap had formed. Group A: the normal flap; Group B: the saline control flap; Group C: the treatment flap with dexamethasone. The survival area of the flaps was measured at 7 days; the apoptotic and necrotic neutrophils, tumor necrosis factor α (TNF-α), and interleukin 10 (IL-10) concentrations were measured. Results The flap survival areas in Groups A and C were larger than those in Group B. The apoptotic neutrophils in Group B were fewer than those in Groups A and C on the 1st and 3rd days after operation; however, they were more in number in Group B than in groups A and C on the 6th day. The necrotic cells in Group B were more in number than those in Groups A and C. In Group B, the plasma TNF-α concentration reached the maximum level at 1 h,while the IL-10 level reached the lowest 3 h after the reperfusion. In Group C, the TNF-α concentration was lower than that in Group B and decreased dramatically at 6 h. The IL-10 concentration was the lowest at 1 h, and increased rapidly at 3 h. Thus, ischemia-reperfusion could injure the flaps, probably through the abnormal action of the neutrophils, such as the disordered secretion of the cytokines and abnormal death course of the neutrophils. Conclusion Dexamethasone can protect the flap from an ischemia-reperfusion injury by its regulation for the neutrophil function.更多还原