间苯三酚对大鼠肾缺血再灌注损伤的保护作用

目的：研究间苯三酚对大鼠肾缺血再灌注损伤（ischemia reperfusion injury, IRI）的保护作用及机制。方法：将雄性Wistar大鼠48只平均分为3组（n=16）：假手术组（Sham组）切除大鼠右肾后，左肾动脉进行同等分离，但不予夹闭；对照组即肾缺血再灌注组（ischemia reperfusion， I/R组），腹腔注射等量的生理盐水，15 min后切除大鼠右肾，无创动脉夹夹闭左肾动脉45 min；实验组即缺血再灌注间苯三酚预处理组（phloroglucinol，PG组），腹腔注射间苯三酚注射液（30 mg/kg），15 min后切除大鼠右肾，无创动脉夹夹闭左肾动脉45 min。每组动物再均分为两个亚组（n′=8）,分别于再灌注后6和24 h将大鼠处死。处死前经下腔静脉取血，检测血清肌酐（secrum creatinine, SCr）、尿素氮（blood urine nitrogen, BUN）；将肾于冠状位切成两半，一半组织制作成组织匀浆，取组织上清液检测丙二醛（malondialdehyde, MDA）、过氧化氢酶（catalase, CAT）、超氧化物歧化酶（superoxide dismutase, SOD）及谷胱甘肽过氧化物酶（glutathione peroxidase, GSH-Px）；另一半组织行石蜡包埋，切片进行病理组织学观察，再灌注后24 h的大鼠肾组织行核转录因子-kapa B(nuclear factor-kapa B, NF-κB)及Caspase 3免疫组织化学检测。结果：再灌注后 6 h，I/R组大鼠血清SCr和BUN分别为(103.9±10.4) μmol/L和(15.2±1.0) mmol/L,PG预处理的SCr及BUN分别为(81.8±13.4) μmol/L和(11.5±1.2) mmol/L；再灌注后24 h，I/R组大鼠血清SCr和BUN分别为(154.9±12.1) μmol/L和(28.1±1.4) mmol/L,PG预处理的SCr及BUN分别为(103.8±5.9) μmol/L和(16.0±1.0) mmol/L；PG预处理组较I/R组明显改善肾功能（P<0.05）；苏木素-伊红染色病理图片可见肾小管损伤较I/R组明显减轻（P<0.05）；经PG处理后大鼠肾组织内MDA含量较I/R组低（P<0.05），SOD及CAT含量较I/R组高（P<0.05），GSH-Px含量较I/R组高（P<0.05）。再灌注后24 h，经间苯三酚处理的肾组织内核因子-kapa B在细胞核内表达的水平明显降低，活化的Caspase-3亦较I/R组有所减少。结论：间苯三酚通过减轻氧化应激和炎性损伤，抑制细胞凋亡，有效改善了大鼠肾IRI。

Protective effect of phloroglucinol on renal ischemia and reperfusion injury

Objective:To investigate the effect and mechanisms of Phloroglucinol ( PG) on renal ische-mia and reperfusion injury (IRI).Methods:Forty-eight male Wistar rats were divided into 3 groups (16 rats per group):sham operated, saline-treated I/R (I/R), and PG-treated I/R (PG).I/R model:Af-ter removing the right kidney , renal I/R injury was induced by clamping the left renal artery for 45 min followed by reperfusion.The rats were administered with PG (30 mg/kg, intraperitoneally) or saline 15 min before renal ischemia .The blood and kidneys were harvested 6 and 24 h after reperfusion .Renal function and histologic changes of serum creatinine (SCr) and blood urea nitrogen(BUN)were assessed. Malondialdehyde (MDA),catalase (CAT),superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) were measured.Nuclear factor-kapa B ( NF-κB) and caspase-3 in the kidneys were also measured.Results:SCr and BUN were (103.9 ±10.4) μmol/L and (15.2 ±1.0) mmol/L in I/R group, and (81.8 ±13.4) μmol/L and (11.5 ±1.2) mmol/L in PG group 6 h after reperfusion .SCr and BUN were (154.9 ±12.1) μmol/L and (28.1 ±1.4) mmol/L in I/R group, and (103.8 ±5.9)μmol/L和(16.0 ±1.0) mmol/L in PG group 24 h after reperfusion.PG treatment significantly attenua-ted renal dysfunction and histologic damage caused by I /R injury(P<0.05).The I/R-induced elevation in kidney MDA level decreased , where as reduced kidney SOD ,CAT and GSH-Px were increased .What is more , the apoptotic tubular cells , the levels of active caspase-3 ,and active nuclear factor kappa B dra-matically decreased after PG treatment .Conclusion:PG protects murine kidney I/R injury by suppres-sing oxidative stress , inflammation , and cell apoptosis .