目的观察淤血预处理对兔肝门静脉阻断模型中肠道淤血-再灌注引起的肠道损伤和肝脏损伤的影响。方法选取雄性日本大耳兔75只,体重2.5~5.0 kg,随机分为五组:假手术组(S组)、淤血-再灌注组(OC组)、预处理A组(OC5组)、预处理B组(OC10组)、...目的观察淤血预处理对兔肝门静脉阻断模型中肠道淤血-再灌注引起的肠道损伤和肝脏损伤的影响。方法选取雄性日本大耳兔75只,体重2.5~5.0 kg,随机分为五组:假手术组(S组)、淤血-再灌注组(OC组)、预处理A组(OC5组)、预处理B组(OC10组)、预处理C组(OC15组),每组15只。S组仅行剖腹手术暴露第一肝门30 min,OC组进行门静脉阻断30 min后开放门静脉。三个预处理组门静脉操作分别为OC5组夹闭5 min,开放5 min;OC10组夹闭10 min,开放10 min;OC15组夹闭15 min,开放15 min,随后阻断门静脉30 min后开放。术后2、8、24 h通过门静脉取血,检测血清中丙二醛(MDA)含量和内毒素、肿瘤坏死因子-α(TNF-α)、丙氨酸转氨酶(ALT)浓度。术后24 h血液样本采集完毕后,再次麻醉并处死以获取回肠末端肠黏膜及肝组织,显微镜下观察病理形态学结构改变。结果与S组比较,术后2、8、24 h OC组、OC5组、OC10组和OC15组血清MDA含量、内毒素、TNF-α、ALT浓度明显升高(P<0.05)。与OC组比较,术后2、8、24 h OC5组、OC10组和OC15组血清MDA含量、内毒素、TNF-α、ALT浓度明显降低(P<0.05)。与OC5组比较,术后2、8、24 h OC10组血清MDA含量、TNF-α、ALT浓度明显降低(P<0.05)。与OC5组比较,术后2、8 h OC10组血清内毒素浓度明显降低(P<0.05)。与OC10组比较,术后8 h OC15组血清MDA含量、ALT浓度明显升高(P<0.05)。与S组比较,OC组、OC5组、OC10组和OC15组肠黏膜损伤Chiu评分明显升高(P<0.05)。与OC组比较,OC5组、OC10组和OC15组黏膜损伤Chiu评分明显降低(P<0.05)。与OC5组比较,OC10组、OC15组的肠黏膜损伤Chiu评分明显降低(P<0.05)。结论淤血预处理可以减轻由于肝门静脉阻断导致的肠道淤血-再灌注损伤,减轻内毒素血症、过度炎性反应及氧自由基对肝脏的损伤。展开更多
BACKGROUND: Nonselective beta-adrenergic blockers decrease portal pressure and prevent variceal hemorrhage. Their effectiveness in preventing varices is unknown. METHODS: We randomly assigned 213 patients with cirrhos...BACKGROUND: Nonselective beta-adrenergic blockers decrease portal pressure and prevent variceal hemorrhage. Their effectiveness in preventing varices is unknown. METHODS: We randomly assigned 213 patients with cirrhosis and portal hypertension (minimal hepatic venous pressure gradient [HVPG] of 6 mm Hg) to receive t imolol, a nonselective beta-blocker (108 patients), or placebo (105 patients). The primary end point was the development of gastroesophageal varices or variceal hemorrhage. Endoscopy and HVPG measurements were repeated yearly. RESULTS: During a median follow-up of 54.9 months, the rate of the primary end point did not differ significantly between the timolol group and the placebo group (39 percent and 40 percent, respectively; P = 0.89), nor were there significant differences in the rates of ascites, encephalopathy, liver transplantation, or death. Serious adverse events were more common among patients in the timolol group than among those in the placebo group (18 percent vs. 6 percent, P = 0.006). Varices developed less frequently among patients with a baseline HVPG of less than 10 mm Hg and among those in whom the HVPG decreased by more than 10 percent at one year and more frequently among those in whom the HVPG increased by more than 10 percent at one year. CONCLUSIONS: Nonselective beta-blockers are ineffective in preventing varices in unselected patients with cirrhosis and portal hypertension and are associated with an increased number of adverse events.展开更多
文摘目的观察淤血预处理对兔肝门静脉阻断模型中肠道淤血-再灌注引起的肠道损伤和肝脏损伤的影响。方法选取雄性日本大耳兔75只,体重2.5~5.0 kg,随机分为五组:假手术组(S组)、淤血-再灌注组(OC组)、预处理A组(OC5组)、预处理B组(OC10组)、预处理C组(OC15组),每组15只。S组仅行剖腹手术暴露第一肝门30 min,OC组进行门静脉阻断30 min后开放门静脉。三个预处理组门静脉操作分别为OC5组夹闭5 min,开放5 min;OC10组夹闭10 min,开放10 min;OC15组夹闭15 min,开放15 min,随后阻断门静脉30 min后开放。术后2、8、24 h通过门静脉取血,检测血清中丙二醛(MDA)含量和内毒素、肿瘤坏死因子-α(TNF-α)、丙氨酸转氨酶(ALT)浓度。术后24 h血液样本采集完毕后,再次麻醉并处死以获取回肠末端肠黏膜及肝组织,显微镜下观察病理形态学结构改变。结果与S组比较,术后2、8、24 h OC组、OC5组、OC10组和OC15组血清MDA含量、内毒素、TNF-α、ALT浓度明显升高(P<0.05)。与OC组比较,术后2、8、24 h OC5组、OC10组和OC15组血清MDA含量、内毒素、TNF-α、ALT浓度明显降低(P<0.05)。与OC5组比较,术后2、8、24 h OC10组血清MDA含量、TNF-α、ALT浓度明显降低(P<0.05)。与OC5组比较,术后2、8 h OC10组血清内毒素浓度明显降低(P<0.05)。与OC10组比较,术后8 h OC15组血清MDA含量、ALT浓度明显升高(P<0.05)。与S组比较,OC组、OC5组、OC10组和OC15组肠黏膜损伤Chiu评分明显升高(P<0.05)。与OC组比较,OC5组、OC10组和OC15组黏膜损伤Chiu评分明显降低(P<0.05)。与OC5组比较,OC10组、OC15组的肠黏膜损伤Chiu评分明显降低(P<0.05)。结论淤血预处理可以减轻由于肝门静脉阻断导致的肠道淤血-再灌注损伤,减轻内毒素血症、过度炎性反应及氧自由基对肝脏的损伤。
文摘BACKGROUND: Nonselective beta-adrenergic blockers decrease portal pressure and prevent variceal hemorrhage. Their effectiveness in preventing varices is unknown. METHODS: We randomly assigned 213 patients with cirrhosis and portal hypertension (minimal hepatic venous pressure gradient [HVPG] of 6 mm Hg) to receive t imolol, a nonselective beta-blocker (108 patients), or placebo (105 patients). The primary end point was the development of gastroesophageal varices or variceal hemorrhage. Endoscopy and HVPG measurements were repeated yearly. RESULTS: During a median follow-up of 54.9 months, the rate of the primary end point did not differ significantly between the timolol group and the placebo group (39 percent and 40 percent, respectively; P = 0.89), nor were there significant differences in the rates of ascites, encephalopathy, liver transplantation, or death. Serious adverse events were more common among patients in the timolol group than among those in the placebo group (18 percent vs. 6 percent, P = 0.006). Varices developed less frequently among patients with a baseline HVPG of less than 10 mm Hg and among those in whom the HVPG decreased by more than 10 percent at one year and more frequently among those in whom the HVPG increased by more than 10 percent at one year. CONCLUSIONS: Nonselective beta-blockers are ineffective in preventing varices in unselected patients with cirrhosis and portal hypertension and are associated with an increased number of adverse events.
