NF—κB在模拟缺血／再灌注诱导人离体胃黏膜上皮细胞凋亡中的作用

目的观察核因子KB（NF—κB）在模拟缺血／再灌注诱导人离体胃黏膜上皮细胞凋亡中活性的变化，并进一步阐明其作用。方法采用人胃黏膜上皮细胞株进行体外培养并传代，细胞以缺氧（5％CO2、1％O2、94％N2）＋兀糖KR液模拟缺血、缺氧，复氧、复糖模拟再灌注诱导胃黏膜上皮细胞凋亡，用流式细胞术、免疫组化法、免疫印迹法观察正常对照组、模拟缺血／再灌注损伤组（I—R组）、NF—κB的抑制剂PDTC预处理组（使用10μmol·L^-1PDTC预处删胃黏膜上皮细胞24h）于模拟缺血1h、再灌注6h后细胞凋亡及NF—κB的表达情况。结果①I—R组细胞凋亡率较正常对照组明显增高（P〈0．01），PDTC预处理组细胞凋亡率较I—R组明显下降（P〈0．01）。②正常对照组胃黏膜上皮细胞核内极少有NF—κB表达，I—R组细胞核内NF—κB表达明显增加，PDTC预处理绀NF—κB核转化现象减轻，胞核染色明显减少。③I—R组与正常对照组比较，胃黏膜上皮细胞核NF—κB蛋白表达水平显著增高（P〈0．01）；PDTC预处理组与I—R组比较，NF—κB蛋白表达水平明显降低（P〈0．01）。结论模拟缺血／再灌注能增加人肖黏膜上皮细胞核内NF—κB的表达，NF—κB的激活具有促进细胞凋产的作用；PDTC叮以抑制细胞凋亡，对人胃黏膜上皮细胞模拟缺血／再灌注损伤有保护作用。

Effect of electroacupuncture preconditioning at “Nèiguān” (内关 PC 6) on gene expression of myocardial opioid receptors in rats with ischemia-reperfusion

Objective To explore protective effects of electroacupuncture at ＂Nèiguān＂ （内关 PC 6） for preconditioning on myocardial ischemia-reperfusion injury （MIRI） and the mechanisms involved. Methods Forty-eight male Wistar rats were randomly divided into a sham operation group （Group N）, a MIRI group （Group M） and an electroacupuncture （EA） group （Group E）. The MIRI model was established by ligating the left anterior descending artery （LAD） for 30 min followed by reperfusion for 120 min. Partition sutures were passed under LAD without ligation for rats in Group N. Rats in Group E were pretreated with electroacupuncture （EA） applied at bilateral ＂Nèiguān＂ （内关 PC 6） for 20 min once a day for 3 consecutive days before ischemia. The infarct size plus the area at risk was evaluated by 2,3,5-triphenyltetrazolium chloride staining, and serum isoenzyme of creatine kinase （CK-MB） and lactate dehydrogenase （LDH） levels were measured by biochemical methods. Myocardium morphological changes were observed under light microscopy. The mRNA expressions of myocardial δ and κ opioid receptors （DOR and KOR） were tested by real-time RT-PCR measurements. Results The myocardial infarct size in Group E was more significantly decreased than that in Group M （P0.05）. The levels of CK-MB [（980？±？92） U/L] and LDH [（2743？±？124） U/L] in Group M were significantly higher than those in Group N [（312？±？41） U/L] and [（530？±？56） U/L], respectively （both P0.01）. The levels of CK-MB [（572？±？70） U/L] and LDH [（1819？±？97） U/L] in Group E were significantly lower than those in Group M （both P0.01）. There were no significant differences in mRNA expressions of DOR and KOR between Group M and Group N （both P0.05）, but DOR expression in Group E was significantly higher than that either in Group M or in Group N （both P0.01 ）. No significant differences were found in KOR expression among the three groups （all P0.05）. Conclusion Up-regulation of expression of δ opioid receptors may be involved in protective effects of EA at Nèiguān （内关 PC 6） for preconditioning on MIRI.