烟碱对大鼠肾脏冷缺血再灌注损伤的作用及机制研究

Effects and mechanism of nicotine on cold ischemia reperfusion injury in rats kidney

摘要:

目的：探讨烟碱对大鼠肾脏冷缺血再灌注损伤（ischemia reperfusion injury，IRI）的保护作用及机制。方法：雄性SD大鼠30只，随机分为假手术组、IRI组和烟碱组（40、400、4 000 ?滋g/kg），每组6只。IRI组制备左肾冷缺血再灌注损伤模型，切除右肾；假手术组仅切除右肾，不行左肾冷缺血再灌注；烟碱组在关腹前腹腔注射烟碱，其余同IRI组。比色法测定血清肌酐（creatinine，Cr）、血尿素氮（blood urea nitrogen，BUN）浓度，酶联免疫吸附测定法（enzyme-linked immunosorbent assay，ELISA）测定血清肿瘤坏死因子-α（tumor necrosis factor，TNF-α）和白细胞介素-1β（interleukin，IL-1β）浓度，免疫印迹法（Western blot，WB）及免疫组织化学法（immunohistochemistry，IHC）测定肾脏细胞内及核内转录因子-κB p65（nuclear transcription factor，NF-κB p65）的表达，苏木精-伊红（hematoxylin and eosin，HE）染色观察肾脏组织病理改变。结果：IRI可导致大鼠肾脏病理改变，引起血清肌酐（P=0.005）、尿素氮（P=0.003）升高，肾小管上皮细胞核内NF-κB p65（P=0.002）增加，血清TNF-α（P=0.011）和IL-1β（P=0.007）增多。术后腹腔注射烟碱可减少肾小管上皮细胞NF-κB p65（P=0.003）核内含量，与IRI组相比，可降低大鼠Cr（P=0.005）、BUN（P=0.004）、TNF-α（P=0.009）和IL-1β（P=0.007）水平，但3个剂量组之间无明显差异。结论：烟碱对肾脏缺血再灌注损伤有保护作用，其机制可能与抑制肾小管上皮细胞NF-κB p65的入核，从而减轻炎症反应，减少TNF-α和IL-1β水平有关。

Abstract:

Objective：To investigate the protective effect and mechanism of nicotine on cold ischemia reperfusion injury in rats. Methods：Totally 30 male SD rats were randomly divided into sham operation group，IRI group and nicotine groups（40，400，4 000 ?滋g/kg），6 rats in each group. The left renal ischemia-reperfusion injury model was set up in IRI group，and the right kidney was removed. The right kidney was removed only in the sham operation group. The nicotine groups injected nicotine into the abdominal cavity before closing it，while the rest were the same as those in the IRI group. The concentrations of serum creatinine and blood urea nitrogen were determined by colorimetric method. The concentrations of interleukin-1 β（IL-1β） and tumor necrosis factor-α（TNF-α） in serum were detected by ELISA. The concentrations of nuclear factor κB（NF-κB） in cell nucleus were detected by Western blot and method of SP immunohistochemistry. HE staining was performed to observe the pathological changes of renal tissue. Results：IRI can cause pathological changes of kidney in rats，increase the level of serum creatinine（P=0.005） and blood urea nitrogen（P=0.003），increase the level of NF-κB p65（P=0.002） in the nucleus of renal tubular epithelial cells，and increase serum TNF-α（P=0.011） and IL-1β（P=0.007）. Compared with those in IRI group，the intraperitoneal injection of nicotine can reduce the content of NF-κB p65（P=0.003） in the nucleus of renal tubular epithelial cells，reduce the level of serum creatinine（P=0.005），blood urea nitrogen（P=0.004），TNF-α（P=0.009） and IL-1β（P=0.007）. But there was no significant difference between the three dose groups. Conclusion：Nicotine has protective effect on renal ischemia reperfusion injury，and its mechanism may be related to the inhibition of the nucleation of NF-κB p65 in renal tubular epithelial cells，reducing the inflammatory reaction and reducing the level of TNF-α and IL-1β.