一种新型大鼠高脂血症急性胰腺炎模型的构建和评价

Construction and evaluation of a new animal model of hypertriglyceridemia acute pancreatitis in rats

背景与目的:目前高脂血症急性胰腺炎(HTG-AP)研究中,动物模型的构建方法尚不统一,且模型制备有一定困难。故本研究探讨一种采用高脂血症诱导物poloxamer-407(P-407)联合L-精氨酸构建大鼠HTG-AP模型的新方法。方法:将72只雄性SD大鼠随机均分为正常对照组和低(0.12 g/kg)、中(0.25 g/kg)、高(0.50 g/kg)3个剂量P-407组。正常对照组大鼠不予干预,其余3组大鼠分别腹腔注射各自剂量的P-407,1次/d诱导高脂血症,每组分别于1、2、4周后随机各取6只大鼠,腹腔注射20%L-精氨酸(2.5 g/kg)2次(间隔1 h)诱导胰腺炎,并于24 h后剖杀,取血检测各组大鼠血清肝肾功能指标以及血清甘油三酯(TG)、总胆固醇(TC)、淀粉酶(AMY)、脂肪酶(LIPA)水平,取胰腺组织观察组织病理学变化并评分。结果:各剂量P-407组与正常对照组比较,血清肝肾功能指标在各时间点均无明显变化(均P>0.05);而血清TG、TC水平在每个时间点均明显升高,且呈时间与剂量依赖性(均P<0.05),其中低剂量P-407组各时间点TG水平未达到HTG-AP血脂标准(TG>11.3 mmol/L),而高、中剂量P-407组分别在实验1、2周后TG水平达HTG-AP血脂标准。各剂量P-407组与正常对照组比较,血清AMY、LIPA明显升高,胰腺病理损伤评分明显增加,且均呈明显的时间与剂量依赖性(均P<0.05)。结论:采用适当剂量的P-407(0.25~5.0 g/kg)联合L-精氨酸的方法可在短时间内(1~2周)构建稳定的大鼠HTG-AP模型。该模型操作简便,可靠性好,可为相关领域的研究提供便利的工具。

Background and Aims:At present,in the research of hypertriglyceridemia acute pancreatitis(HTG-AP),the methods for generating animal models are diverse,and the models are also difficult to construct.Therefore,this study was conducted to develop a new method for establishing a rat HTG-AP model by using the hyperlipidemia inducing agent poloxamer-407(P-407)combined with L-arginine.Methods:Seventy-two male SD rats were equally randomized into normal control group,and low dose P-407(0.12 g/kg),medium P-407 dose(0.25 g/kg)and high P-407 dose(0.50 g/kg)group.Rats in normal control group did not receive any treatment,and those in the other 3 groups underwent intraperitoneal injection of respective doses of P-407 once per day to induce hyperlipidemia.Six rats in each group were randomly selected on 1 week,2 and 4 weeks later respectively,and underwent intraperitoneal injection of 20%L-arginine(2.5g/kg)twice(a 1-h time interval)to induce acute pancreatitis,and were sacrificed 24 h later,and then the blood samples were taken for measurement of the serum levels of liver and renal function parameters as well as the serum levels of triglyceride(TG),total cholesterol(TC),amylase(AMY)and lipase(LIPA),and the pancreatic tissues were harvested for observation and scoring of the pathological changes of pancreas.Results:In each P-407 dose group compared with normal control group,the serum levels of liver and renal function parameters showed no significant changes at each time point(all P>0.05);the serum levels of TG and TC levels were significantly increased at each time point with a time-and dose-dependent manner(all P<0.05),in which,the TG level in low P-407 dose group did not reach a blood lipid standard of HTG-AP(TG>11.3 mmol/L)at each time point,while the TG level in high and medium P-407 dose group reached the blood lipid standard of HTG-AP from 1 week and 2 weeks after the experiment,respectively.In each P-407 dose group compared with normal control group,the serum levels AMY and LIPA were all significantly increased and the scores for pancreatic pathological injury were all significantly elevated,and all these effects presented a time-and dose-dependent manner(all P<0.05).Conclusion:Using a suitable dose of P-407(0.25-0.50 g/kg)combined with 20%L-arginine(2.5 g/kg)can successfully construct a stable rat HTG-AP model within a short period of time(1 week to 2 weeks).This model is easy to be replicated with good reproducibility,and can provide a convenient tool for studies in the relevant fields.