血管紧张素Ⅱ和胡索酸-3-氨基丙腈联合诱导小鼠建立腹主动脉瘤模型的特点

Effect of angiotensin Ⅱ and β aminopropionitrile monofumarate to induce abdominal aortic aneurysm models in mice

目的观察血管紧张素Ⅱ(AngⅡ)和胡索酸-3-氨基丙腈(BAPN)联合诱导小鼠建立腹主动脉瘤(AAA)模型的特点和可行性。方法实验于2017年1—6月在武汉大学人民医院中心实验室进行。将30只C57BL6小鼠采用随机数字表法分为空白对照组、模型A组和模型B组,每组10只。模型A组小鼠皮下植入微量渗透泵持续泵入AngⅡ(1μg·kg^(-1)·min^(-1))28 d,同时食用含0.25%BAPN饲料饲喂28 d;模型B组小鼠食用含0.25%BAPN饲料饲喂27 d,第28天皮下泵入AngⅡ24 h;空白对照组皮下持续泵入生理盐水,食用普通饲料。动脉瘤破裂死亡小鼠立即取材,第29天仍存活小鼠处死取材。取材后,测量小鼠腹主动脉直径,冰冻切片进行活性氧(ROS)染色,石蜡切片进行弹性纤维染色,免疫组化染色检测基质金属蛋白酶2(MMP-2)表达。结果模型A组小鼠AAA发生率为70.0%,高于模型B组小鼠AAA发生率22.2%(P<0.01),模型B组腹主动脉直径与空白对照组比较差异无统计学意义(P>0.05),模型A组腹主动脉直径大于模型B组(P<0.05);ROS染色显示模型A、B组比对照组腹主动脉组织中ROS表达增多;弹性纤维染色显示模型A、B组与对照组比较弹性纤维有断裂及排列紊乱;免疫组化染色显示模型A、B组比对照组MMP-2表达增多。结论通过血管紧张素Ⅱ持续皮下泵入和BAPN联合可以诱导建立小鼠AAA模型。

Objective To investigate the characteristic and feasibility of mice model of abdominal aortic aneurysm （AAA） induced by Angiotensin Ⅱ （Ang Ⅱ ） combining with β aminopropionitrile monofumarate （BAPN）. Methods Thirty C57BL6 mice were randomly divided into control group, model A group and model B group, with 10 mice in each group. The model A group was subcutaneous infused with Ang Ⅱ through the implantation of osmotic pumps for 28 days at a rate of 1 μg · kg^-1· min^-1, meanwhile being fed with a diet containing 0.25% BAPN for 28 days. The model B group was fed with a diet containing 0.25 % BAPN for 27 days, followed by Ang Ⅱ infusion for 24h at a rate of 1 μg · kg^-1· min^- 1. The control group was infused with saline and fed with a chow diet. The incidence of AAA, diameter of abdominal aortic, ROS staining and elastin staining, the physiopathologic changes of the abdominal aorta were compared between model groups and the control group. The expression of MMP-2 was detected with immunohistochemical staining. Results The incidence of AAA in model A group and model B group was 70.0% and 22.2%, respectively. Diameter of abdominal aortic in model A group was greater com- pared with the control group （P 〈0. 01 ）, while the comparison between model B group and the control group was not statistically significant. And diameter of abdominal aortic in model A group was greater compared with model B group （P 〈 0.05）. ROS staining showed that the expression was up regulated in model groups compared with the control group. Elastin staining showed that elastic fibers were degraded and disordered in model groups. Immunohistochemical staining showed that the expression ofMMP 2 increased in model groups compared with the control group. Conclusion The AAA model could be successfully established with Ang Ⅱ and BAPN.