脑死亡状态对大鼠肝脏损伤的影响

目的　探讨大鼠脑死亡状态与肝脏损伤之间的关系。方法　将 50只大鼠随机分为空白对照组 (C)、低血压状态假手术组 (E1 )、脑死亡实验组 (E2 )。各组动物分别于辅助呼吸 1、3h采血检测丙氨酸氨基转移酶 (ALT)、天冬氨酸氨基转移酶 (AST)及透明质酸 (HA)、内皮素 1 (ET 1 ) ,辅助呼吸 4h取肝组织行形态学检查。结果　 1、3h血清ALT、AST以及HA、ET 1水平E2组较C、E1组显著升高 (P <0 .0 5) ;E2组中 3h较 1h显著升高 (P <0 .0 5)。电镜下E2组大鼠肝脏Kuffer细胞明显活化 ,肝窦内皮细胞与基质部分脱落、肝窦内皮窗孔扩大 ;C、E1组Kuffer细胞活化不明显 ,内皮细胞基本完整。结论　大鼠脑死亡状态能明显导致肝实质细胞与非实质细胞损伤     

葛根素对脑死亡大鼠肝脏的保护作用

目的 探讨葛根素对脑死亡状态下大鼠的肝脏的保护作用.方法 SD大鼠随机分为3组:模型组,采用渐进式颅内加压法建大鼠脑死亡模型;葛根素组,建脑死亡模型后给予葛根素;假手术组,仅做假手术,不建脑死亡模型.分别于造模后2 h和4 h取材,检测血清中ALT,AST,TNF-α和IL-6水平,并做肝脏病理形态学观察.结果 与假手术组比较,模型组与葛根素组大鼠血清ALT,AST,TNF-α和IL-6水平均明显升高(均P<0.05),同组不同时间点比较显示,模型组与葛根素组大鼠上述指标且均呈进行性升高(均P<0.05),在相同时间点上,葛根素组大鼠上述指标明显低于模型组大鼠(P<0.05);病理学检查显示,模型组与葛根素组肝脏均出现不同程度的损伤,但葛根素组损伤程度明显轻于模型组.结论 葛根素对脑死亡状态下大鼠肝脏具有作用.     

多巴胺预处理对脑死亡大鼠肾免疫原性的影响

目的　观察用多巴胺预处理对脑死亡大鼠肾免疫原性的影响。方法　对脑死亡大鼠静脉内持续滴注多巴胺 ,剂量分别为 2、6、10和 14 μg·kg-1·ml-1,6h后取出肾脏 ,进行免疫组化分析。结果　用多巴胺预处理后 ,脑死亡大鼠的肾脏单核吞噬细胞浸润、主要组织相容性复合物Ⅱ类抗原的表达以及P 选择素的表达受到抑制 ,其抑制程度随多巴胺的用量增加而加大。结论　多巴胺的预处理可以明显降低脑死亡大鼠肾脏的免疫原性     

The influence of psychic stress and brain death on the intestinal receptor for the cobalamin–intrinsic factor complex in rats

This study was undertaken to evaluate the effects of psychic stress on receptor activity. The model studied was the intestinal receptor for the intrinsic factor — cobalamin complex of the rat. Several kinds of stress tended to decrease the activity of the receptor, but not quite significantly. Brain death caused significant decrease. Pregnancy and oestradiol treatment were included as positive controls as they significantly increased receptor activity.     

羟丁酸钠对新生大鼠缺血缺氧性脑损害的干预作用

目的 观察羟丁酸钠对新生大鼠缺血缺氧性脑损害的干预作用。方法 新生7dSD大鼠随机分为假手术组(S组)、生理盐水对照组(C组)、羟丁酸钠组(γ组),7组又分为γ_1、γ_2、γ_3组。各组20只。采用Rice法制作新生大鼠缺血缺氧性脑损害模型。C组缺血缺氧后即刻腹腔注射生理盐水,每日3次;γ_1、γ_2、γ_3组分别注射羟丁酸钠50、100和200 mg/kg,用法同C组。观察大鼠缺血缺氧后28d内存活率、脑部形态学改变、左/右大脑半球重量比值、左大脑半球含水量和学习记忆能力(Y-迷宫法)。结果 (1)C组动物存活率(60％)明显低于其余各组(P<0.05)。(2)学习记忆能力测试表明:C组达标率(41.7％)明显低于其他各组(P<0.05);γ_1组与γ_2、γ_3和S组相比,学习记忆能力较差;(3)C组和γ_1组左/右大脑半球湿重之比值明显小于γ_2、γ_3和S组(P<0.01或P<0.05);各组左侧大脑半球含水量差异无显著性(P<0.05);C组左侧大脑半球液化坏死后空洞发生率明显高于其他各组(P<0.05)。结论 羟丁酸钠对新生大鼠具有抗缺血缺氧性脑损害的作用。     

兔脑死亡状态对肝脏蛋白质表达谱的影响

目的 分析兔脑死亡状态下肝脏存在的差异蛋白质,为揭示脑死亡状态下肝脏损伤的影响因素提供实验依据.方法 采用缓慢颅内加压法建立兔脑死亡模型.提取脑死亡后6h标本蛋白质进行双向凝胶电泳.利用PDQuest凝胶图像分析软件对图像进行分析.将两组间差异在2倍以上的蛋白质点行基质辅助激光解析离子化飞行时间质谱鉴定.在NCBI数据库中检索,鉴定出相应的蛋白质,并用蛋白印迹法进行验证.结果 双向凝胶电泳显示,假手术组可检测到大约(973±34)个蛋白质点,脑死亡组可检测到大约(987±38)个蛋白质点.经成组比较共计有52个明显差异表达的蛋白质点,与假手术组相比,上调29个,下调23个.10个差异蛋白点分别为线粒体醛脱氢酶、过氧化物酶6、3磷酸肌醇依赖性蛋白激酶1、3-巯基丙酮酸硫基转移酶、乙醇脱氢酶、二氢嘧啶酶相关蛋白4、Runt相关转录因子1、无机焦磷酸酶、谷氨酸-半胱氨酸连接酶的调节亚基、微粒细胞色素B5.其中,RUNX1是我们比较关注的一个蛋白.通过蛋白印迹法对RUNX1在各组织中的表达情况进行验证发现,随着脑死亡时间的延长,RUNX1在肝脏中的表达逐渐减少.结论 双向凝胶电泳结合质谱鉴定是差异蛋白质组学研究的可靠平台和有力工具,鉴定出的蛋白质RUNX1可能与脑死亡后肝脏损伤的发生、发展有关,有助于对脑死亡后肝脏损伤机制的了解.     

胆绿素对脑死亡致大鼠肺损伤的影响

目的 评价胆绿素对脑死亡致大鼠肺损伤的影响.方法 成年雄性清洁级Wistar大鼠23只,体重250～300 g,随机分为3组,假手术组(S组,n=7)仅向大鼠颅内置入Fogarty导管;脑死亡组(BD组,n=8)和胆绿素组(B组,n=8)向大鼠颅内置入Fogarty导管,通过膨胀球囊诱导脑死亡,膨胀球囊后30 min确认脑死亡情况,发生脑死亡后分别腹腔注射生理盐水1 ml或胆绿素35 mg/kg.分别于给予胆绿素前、后间断采集动脉血样,进行血气分析,计算PaO2/FiO2,并测定血浆胆红素浓度.给予胆绿素后1.5 h处死大鼠,取肺组织,测定MDA含量、SOD活性、总抗氧化能力、肺组织细胞凋亡情况及胆绿素还原酶的表达水平,对细胞凋亡情况进行免疫组化评分.结果 与S组比较,BD组PaO2/FiO2、SOD活性和总抗氧化能力降低,MDA含量和凋亡细胞免疫组化评分升高(P＜0.05);与BD组比较,B组PaO2/FiO2、胆红素浓度、SOD活性、总抗氧化能力和胆绿素还原酶表达水平升高,MDA含量和凋亡细胞免疫组化评分降低(P＜0.05).结论 外源性给予胆绿素可减轻脑死亡致大鼠肺损伤,其机制与抑制肺组织氧化应激反应和细胞凋亡有关.     

大鼠肝切除术时阻断肝门血流对细菌易位的影响

目的　研究肝切除术时阻断肝门血流对细菌易位和血浆内毒素水平的影响,并探讨其机理。 方法　分别观察了６２ 只大鼠在阻断和不阻断肝门的情况下,肝切除术后６ 小时血中的内毒素含量和细菌易位以及远端回肠组织学变化。 结果　假手术组（ｓｈａｍ ｏｐｅｒａｔｉｏｎ,Ｓｈ 组） 、单纯切肝组（ｈｅｐａｔｅｃｔｏｍｙ,Ｈｔ 组）、阻断切肝组（ｈｅｐａｔｅｃｔｏｍｙ ｕｎｄｅｒ ｐｏｒｔａｌｔｒｉａｄ ｃｌａｍｐｉｎｇ,Ｐｃ＋ Ｈｔ 组） 术后６ 小时腔静脉血、门静脉血的血浆内毒素含量依次升高,分别为０－０２０ ±０－００４、０－０２１±０－００５;０－０２３±０－００６、０－０２６±０－００８ ;０－０２９±０－０１１、０－０３４ ±０－０１２ Ｅｕ／ｍｌ。３ 组术后细菌学结果：Ｓｈ 组２０ 只大鼠术后６ 小时所有标本培养均无细菌生长;Ｈｔ 组２１ 只大鼠术后６ 小时肠系膜淋巴结的细菌易位率为１９％ （４／２１）,腔静脉血为１０％ （２／２１）,门静脉血为１０％ （２／２１）;Ｐｃ＋ Ｈｔ 组则分别为３８％ （８／２１） 、１９％ （４／２１）、２４％ （５／２１）。在Ｓｈ 组、Ｈｔ 组肠粘膜损伤较轻,而Ｐｃ＋ Ｈｔ 组２１ 只大鼠则损伤明显。 结论　肝切除术时阻     

改良大鼠渐进性脑死亡模型的制作

目的 总结制作大鼠渐进性脑死亡模型的技巧并改良此模型的制作方法.方法 对经典Pratschke术式的麻醉、插管、颅内加压、脑死亡判断等环节进行探讨,建立Wistar大鼠的渐进性脑死亡模型.结果 所有动物在诱导脑死亡过程中均出现较一致的血压变化规律:诱导后期平均动脉压开始急剧升高,于颅内加压后(11±2)min时达到峰值(190±15)mm Hg,其后血压急剧下降,(20±3)min时达到谷值(70±16)mm Hg,与诱导前平均动脉压(110±18)mm Hg比较,其峰值和谷值差异均具有统计学意义(P＜0.05).共诱导40例大鼠脑死亡,37例能成功维持正常血压达6 h,手术成功率92.5%(37/40).结论 与经典Pratschke术式比较,该术式降低难度,提高手术成功率,是一种较稳定、可靠的大鼠脑死亡模型.     

The influence of age and administration rate on the brain sensitivity to propofol in rats

Background: It is well established that the dose of propofol for induction of anaesthesia is influenced by patient age. This may be explained by differences in pharmacokinetics or pharmaco-dynamics. To evaluate the effect of age on propofol pharmaco-dynamics, the brain concentration of propofol at the time of an EEG end-point was used as a measure of CNS sensitivity.
Methods: Ninety-five rats were assigned to 4 groups. Anaesthesia was induced by continuous propofol infusion at different rates. The dose of propofol and duration of anaesthesia were determined from 23 up to 776 days of age. The rats were killed at 23,287 or 776 days of age at the EEG end-point and samples of cerebral cortex, midbrain, cerebellum, serum and fat tissue were submitted to HPLC analysis of propofol concentrations.
Results: The induction dose of propofol varied with age and administration rate. Young animals needed a higher dose of propofol. Old animals had higher brain concentrations of propofol at the EEG end-point than young animals. However, propofol concentrations in serum were higher in young animals. The propofol concentration in the brain was influenced by the administration rate.
Conclusion: The dose of propofol for induction of anaesthesia in rats is influenced by animal age and administration rate. Young animals need a larger induction dose than old rats, but are more sensitive as measured by the brain concentration of propofol. The larger induction dose in young rats when compared with adults is explained by pharmacokinetic differences rather than by pharmacodynamic changes.     

异氟醚吸入对老年大鼠长时程增强和脑源性神经营养因子的影响

目的通过观察异氟醚麻醉后老年大鼠海马长时程增强(LTP)和脑源性神经营养因子(BDNF)的变化,探讨术后认知功能障碍(POCD)的可能机制。方法健康雄性20月龄SD大鼠72只,随机分为异氟醚处理组(I组)和对照组(C组),每组36只。I组大鼠异氟醚吸入及维持浓度为1.2%,维持麻醉3h,以大鼠翻正反射的消失和恢复视为麻醉的开始和结束;C组大鼠不吸入麻醉药。I组大鼠分别于麻醉后7和14d断头,C组大鼠直接断头,常规切取海马组织,制备厚500μm的海马脑片,进行LTP斜率和幅值的测定,Western blot法检测BDNF表达水平。结果与C组比较,异氟醚处理后7和14dI组LTP的斜率和幅值均明显下降(P0.05)。与处理后7d比较,处理后14dI组LTP斜率和幅值均有明显升高(P0.05)。与C组比较,处理后7和14dI组BDNF表达水平明显下降(P0.05)。与处理后7d比较,处理后14dI组BDNF表达水平明显升高(P0.05)。结论异氟醚麻醉后,老年大鼠学习记忆能力损害可能持续14d以上,LTP的改变可能参与POCD的发生机制,并且与BDNF表达水平的降低有关。     

内毒素/脂多糖对烫伤大鼠休克期肝脏脂肪代谢的影响

目的观察内毒素/脂多糖(LPS)对烫伤大鼠休克期肝脏脂肪代谢的影响。方法采用30%TBSAⅢ度烫伤大鼠模型,随机分为单纯烫伤组(烫伤组)和烫伤后LPS攻击组(攻击组),另设假烫对照组(对照组),每组20只。攻击组大鼠于烫伤后2h腹腔注射LPS,3.0mg/kg.伤后24、48h分别检测3组大鼠血浆LPS、肿瘤坏死因子(TNF)α、游离脂肪酸(FFA)含量和肝组织内腺苷三磷酸(ATP)、甘油三酯(TG)及丙二醛(MDA)含量,并进行肝组织形态学观察。结果对照组大鼠假烫后24、48h,血浆FFA水平分别为(0.4±0.3)、(0.5±0.3)mmol/L,烫伤组分别为(0.9±0.3)、(1.2±0.5)mmol/L,攻击组大鼠伤后增加至(2.3±0.3)、(2.5±0.4)mmol/L,后两组之间比较差异有统计学意义(P<0.01).伤后48h,烫伤组和攻击组的肝组织TG含量分别为(242±27)mmol/g和(530±30)mmol/g,ATP含量分别为(6.0±2.4)μmol/g和(1.7±0.5)μmol/g,组间比较差异有统计学意义(P<0.01).组织形态学检查见,烫伤组大鼠肝细胞脂肪变性和线粒体损伤程度明显轻于攻击组,对照组肝细胞形态正常。结论烧伤后早期LPS打击可引发脂源性能量利用障碍,并加剧肝脏脂肪变性。     

Synergistic effects of brain death and liver steatosis on the hepatic microcirculation

BACKGROUND: The routine transplantation of steatotic livers could potentially mitigate the donor shortage, but so far is associated with a high rate of graft dysfunction. Steatosis and brain death have been perceived as independent risk factors, but they may synergistically target the hepatic microcirculation. This study compares the effects of brain death on the microcirculation of steatotic and normal livers. METHODS: Brain death was induced in obese and lean Zucker rats. Lean and obese sham-operated animals served as controls. Liver microcirculation was investigated using intravital fluorescence microscopy. Serum liver enzyme and reduced glutathione, expression of P-selectin, ICAM-1 and VCAM-1 mRNA in the liver were determined. The ultrastructural alterations were compared by electron microscopy. RESULTS: In nonbrain-dead animals, liver steatosis was associated with smaller sinusoidal diameters, but did not impair sinusoidal perfusion. During brain death, sinusoidal diameter and perfusion were reduced in normal and, to a greater extent, in steatotic livers. Also, more leukocytes were recruited to the microvasculature of steatotic livers than to normal livers in brain-dead state. The highest liver enzyme activities and the lowest hepatic GSH concentrations were measured in brain-dead animals with steatotic livers; only in these organs was endothelial cell swelling regularly observed. In brain-dead state, only the P-selectin mRNA expression was increased in steatotic livers as compared to normal livers. CONCLUSIONS: Brain death amplifies the adverse effects of steatosis on the hepatic microcirculation. Our results underline the need for therapeutic intervention in brain-dead state when steatotic livers are to be used for transplantation.     

Similar liver transplantation survival with selected cardiac death donors and brain death donors

Background:

The outcome of orthotopic liver transplantation (OLT) with controlled graft donation after cardiac death (DCD) is usually inferior to that with graft donation after brain death (DBD). This study compared outcomes from OLT with DBD versus controlled DCD donors with predefined restrictive acceptance criteria.

Methods:

All adult recipients in the Netherlands in 2001–2006 with full‐size OLT from DCD (n = 55) and DBD (n = 471) donors were included. Kaplan–Meier, log rank and Cox regression analyses were used.

Results:

One‐ and 3‐year patient survival rates were similar for DCD (85 and 80 per cent) and DBD (86·3 and 80·8 per cent) transplants (P = 0·763), as were graft survival rates (74 and 68 per cent versus 80·4 and 74·5 per cent; P = 0·212). The 3‐year cumulative percentage of surviving grafts developing non‐anastomotic biliary strictures was 31 per cent after DCD and 9·7 per cent after DBD transplantation (P < 0·001). The retransplantation rate was similar overall (P = 0·081), but that for biliary stricture was higher in the DCD group (P < 0·001). Risk factors for 1‐year graft loss after DBD OLT were transplant centre, recipient warm ischaemia time and donor with severe head trauma. After DCD OLT they were transplant centre, donor warm ischaemia time and cold ischaemia time. DCD graft was a risk factor for non‐anastomotic biliary stricture.

Conclusion:

OLT using controlled DCD grafts and restrictive criteria can result in patient and graft survival rates similar to those of DBD OLT, despite a higher risk of biliary stricture. Copyright © 2010 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.     

吸入一氧化碳对大鼠脑死亡致肺损伤的影响

Objective To investigate the effects of carbon monoxide (CO) inhalation on lung injury induced by brain death (BD) in rats. Methods Adult male Wistar rats weighing 250-300 g were used in this study. The animals were anesthetized with intraperitoneal pentobarbital sodium 60 mg/kg, tracheostomized and mechanically ventilated (VT 10 ml/kg, RR 50 bpm, PEEP 2 cm H2O). A balloon-tip catheter was placed in the cranium. Twenty-four rats in which Fogarty catheter was successfully placed in the cranium without complication were randomly divided into 3 groups ( n = 8 each) : group I sham operation (group S) ; group II BD and group Ⅲ BDCO. BD was induced by increase in intracranial pressure produced by inflating the balloon at the tip of the catheter. In group S the balloon of the catheter was not inflated. The animals inhaled 40% O2 for 150 min. In group BD, BD was induced and confirmed at 30 min after inflation of the balloon. Then 40% O2 was inhaled for 120 min. In group BDCO, 40% O2 and 0.025% CO were inhaled for 120 min after BD was confirmed at 30 min after balloon inflation. At the end of the experiment the animals were killed. Arterial blood samples were obtained for blood gas analysis before anesthesia (basline), immediately after confirmation of BD, and at 30, 60, 90 and 120 min of CO inhalation. Blood was collected for determination of plasma TNF-α, IL-6 and IL-10 concentrations at 120 min of CO inhalation. The lungs were obtained for determination of W/D lung weight ratio, and MPO activity in the lung tissue and microscopic examination. Lung injury scores were calculated. Results PaO2/FiO2 was stable during the 150 min in group S. Brain death significantly decreased PaO2/FiO2 at 30 min after balloon inflation. PaO2/FiO2 was gradually decreasing during the 120 min in group BD. CO inhalation prevented PaO2/FiO2 from decreasing further. W/D lung weight ratio and MPO activity were significantly higher in group BD than in group S and BDCO. The lung injury score (1 = normal, 4= severely injured) and plasma TNF-αα IL-6 and IL-10 concentrations were significantly higher in group BD than in group S. CO inhalation ameliorated the BD-induced lung injury and attenuated the increase in plasma TNF-a and IL-6 concentration. Plasma IL-10 concentration was significantly higher in group BDCO than in group BD. Conclusion CO inhalation can ameliorate acute lung injury induced by BD through decreasing the local and systemic inflammatory response.