间断低氧预适应对大鼠肝切除缺血再灌注肝脏凋亡相关蛋白Bcl-2和Bax表达的影响

发布时间：2018-02-13 23:13

本文关键词： 间断低氧预适应缺血再灌注损伤 Bcl-2 Bax 凋亡肝脏　出处：《扬州大学》2014年硕士论文　论文类型：学位论文

【摘要】：1、目的建立大鼠肝切除残余肝脏缺血再灌注损伤模型,观察术前间断低氧预适应对残余肝脏中凋亡相关蛋白Bcl-2和Bax表达的影响。进而探讨间断低氧预适应对肝切除合并缺血再灌注损伤肝脏的保护机制,为其在肝脏外科临床应用寻找理论依据。 2、方法健康SD大鼠20只,用于大鼠肝脏解剖和肝切除缺血再灌注损伤模型的练习,计算模型术后一周生存率。能够建立稳定的模型后,另取SD大鼠54只,随机分为肝切除组(PH组)、肝切除残余肝脏缺血再灌注组(IR组)和术前间断低氧预适应组(IHP组)。分别结扎PH组大鼠肝脏左叶和中叶根部后将其切除,切除部分湿重约占整个肝脏湿重的70%。残余肝脏缺血再灌注组(IR组),即在夹闭肝十二指肠韧带、阻断入肝血流情况下,按照PH组的方法切除肝脏的左叶和中叶。肝门阻断20min后开放血流,残余肝脏发生了缺血再灌注过程。间断低氧预适应组(IHP组),术前一周将大鼠置于氧气体积分数10%的低氧环境中接受低氧刺激,每天1h。一周后在肝门阻断下行肝切除术(同IR组)。各组分别于术后12、24和48h取下腔静脉血和残余肝组织进行检测。用全自动生化分析仪检测血清谷丙转氨酶(ALT)、谷草转氨酶(AST)含量,间接反映肝脏受损程度。采用免疫组织化学方法检测残余肝组织凋亡相关蛋白Bcl-2和Bax表达情况,以积分光密度来反映其表达强度。 3、结果 1.肝大部切除合并残余肝脏缺血再灌注损伤模型术后七天生存率为93.3%。麻醉复苏后大鼠健康存活,未发现明显手术并发症。 2.术后肝功能在术后每个时间点,IR组和IHP组大鼠血清ALT和AST水平均高于PH组,但IHP组明显低于IR组,差异均具有统计意义(P0.05)。 3.术后残余肝脏组织中Bcl-2和Bax表达’术后每个时间点各组大鼠肝脏中Bcl-2蛋白表达的积分光密度相比,IHP组均显著高于PH组和IR组(差异有统计学意义,P0.05)。虽然PH组在术后每个时间点也均高于IR组,但仅在术后48小时有统计学差异(P0.05),术后12小时和24小时差异无统计学意义(P0.05)。Bax蛋白表达的积分光密度与Bcl-2相反,IHP组在各时间点均低于IR组,但高于PH组。差异具有统计学意义(P0.05)。 4、结论通过临时夹闭肝十二指肠韧带,可建立稳定、可靠的肝切除残余肝脏缺血再灌注模型(肝再生合并缺血再灌注损伤模型)。间断低氧预适应对残余肝脏缺血再灌注损伤具有保护作用,其途径可能是通过促进抗凋亡蛋白Bcl-2表达和抑制促凋亡蛋白Bax表达,来减少肝细胞凋亡。
[Abstract]:1. Purpose. A rat model of hepatic ischemia-reperfusion injury after hepatectomy was established. To observe the effect of intermittent hypoxia preconditioning on the expression of apoptosis-related protein Bcl-2 and Bax in residual liver, and to explore the protective mechanism of intermittent hypoxia preconditioning on liver injury after hepatectomy and ischemia reperfusion injury. To find a theoretical basis for its clinical application in liver surgery. 2, method. Twenty healthy Sprague-Dawley (SD) rats were used for the exercise of liver anatomy and hepatectomy ischemia-reperfusion injury model, and the one-week survival rate of the model was calculated. After establishing a stable model, another 54 SD rats were taken out. The rats were randomly divided into hepatectomy group (PH group), hepatectomy residual liver ischemia reperfusion group (IR group) and intermittent hypoxia preconditioning group (IHP group). Zuo Ye of liver and middle lobe root of PH group were ligated respectively. The partial wet weight of the liver was about 70% of the total wet weight of the liver. In the residual liver ischemia-reperfusion group, the IR group was in the condition of clamping the ligaments of the liver and duodenum and blocking the blood flow into the liver. Zuo Ye and middle lobe of the liver were resected according to PH group. The hepatic portal was blocked for 20 minutes and the blood flow was opened. The rats in the intermittent hypoxic preconditioning group were exposed to hypoxic stimulation in hypoxic environment with oxygen volume fraction 10% one week before operation. After 1 hour a day, the hepatic resection was performed at hepatic hilus occlusion (IR group). The blood samples of inferior vena cava and residual liver tissue were taken at 1224 and 48 hours after operation. The serum alanine aminotransferase (alt) and alanine aminotransferase (alt) were measured by automatic biochemical analyzer. Immunohistochemical method was used to detect the expression of apoptosis-related protein Bcl-2 and Bax in residual liver tissue, and the intensity of expression was reflected by integral optical density. 3, result. 1. The survival rate of the model of hepatic ischemia reperfusion injury after subtotal hepatectomy was 93.30.The survival rate of rats after anesthesia and resuscitation was healthy and there were no obvious operative complications. 2. The levels of serum ALT and AST in IR group and IHP group were higher than those in PH group at each time point after operation, but those in IHP group were significantly lower than those in IR group. The difference was statistically significant (P 0.05). 3. Expression of Bcl-2 and Bax in residual liver tissue after operation: the integral optical density of Bcl-2 protein expression in the liver of each group was significantly higher than that of PH group and IR group at each time point after operation (P < 0.05), although the expression of Bcl-2 protein in PH group was significantly higher than that in PH group and IR group (P < 0.05). Each time point after operation was also higher than that in IR group. However, there was a significant difference only at 48 hours after operation (P 0.05). There was no significant difference between 12 hours and 24 hours after operation. The integral optical density of P0.05U. Bax protein expression in Bcl-2 group was lower than that in IR group at all time points, but higher than that in PH group. The difference was statistically significant (P 0.05). 4. Conclusion. Stability can be established by temporarily clipping the hepatoduodenal ligament. A reliable model of residual liver ischemia-reperfusion injury after hepatectomy (liver regeneration combined with ischemia-reperfusion injury). Intermittent hypoxic preconditioning has protective effect on residual liver ischemia-reperfusion injury. The pathway may be to reduce hepatocyte apoptosis by promoting the expression of anti-apoptotic protein Bcl-2 and inhibiting the expression of pro-apoptotic protein Bax.
【学位授予单位】：扬州大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R657.3

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