血管紧张素-Ⅱ联合β-氨基丙腈腹腔注射建立主动脉夹层小鼠模型

Establishing a mouse model of aortic dissection by intraperitoneal injection of angiotensin-Ⅱ combined with β-aminopropionitrile

目的血管紧张素-Ⅱ(Ang-Ⅱ)联合β-氨基丙腈(BAPN)腹腔注射建立小鼠主动脉夹层模型。方法 80只C57BL/6J小鼠(3周龄,雄性)分为对照组和7个实验组,分别为:Ang-Ⅱ组、BAPN 0.1 g/kg组、BAPN 0.33 g/kg组、BAPN 0.67 g/kg组、Ang-Ⅱ+BAPN 0.1 g/kg组、Ang-Ⅱ+BAPN 0.33 g/kg组、Ang-Ⅱ+BAPN0.67 g/kg组。对照组每8 h给予腹腔注射0.9%氯化钠注射液0.1 ml,Ang-Ⅱ组每8 h腹腔注射4.0 mg/kg Ang-Ⅱ,3种不同剂量的BAPN组每日分别给予腹腔注射0.1、0.33、0.67 g/kg BAPN, 3个联合用药组分别在每8 h腹腔注射4.0 mg/kg Ang-Ⅱ的基础上,分别给予腹腔注射0.1、0.33、0.67 g/kg BAPN。每组均于相同时间点应用鼠尾测压器检测并记录小鼠血压,持续14 d,中途死亡小鼠直接解剖,取出主动脉。14 d后处死小鼠,取出主动脉行病理观察。结果未注射Ang-Ⅱ的3个BAPN组小鼠血压与对照组比较差异无统计学意义(P>0.05);注射Ang-Ⅱ的4个组血压与对照组比较差异有统计学意义(P<0.05)。对照组无主动脉夹层形成,HE染色显示血管壁结构完整;7个实验组HE染色显示部分小鼠血管壁弹力纤维破坏,假腔形成,炎性细胞浸润,提示主动脉夹层形成。BAPN 0.1 g/kg组、BAPN 0.33 g/kg组、BAPN 0.67 g/kg组,随着BAPN注入剂量的增加,主动脉夹层的发生率逐渐上升,分别为10%、30%、50%,部分小鼠因主动脉破裂死亡,3组分别为0、1、4只;Ang-Ⅱ组和Ang-Ⅱ+BAPN0.1 g/kg组主动脉夹层发生率较低(均为30%),死亡分别为1、0只;Ang-Ⅱ+BAPN 0.33 g/kg组和Ang-Ⅱ+BAPN0.67 g/kg组主动脉夹层发生率分别为70%和80%,Ang-Ⅱ+BAPN 0.33 g/kg组死亡2只,而Ang-Ⅱ+BAPN 0.67g/kg组8只形成主动脉夹层的小鼠均死亡。Ang-Ⅱ+BAPN 0.33 g/kg组主动脉夹层发生率高,死亡率不高,符合小鼠主动脉夹层模型的要求。结论 Ang-Ⅱ联合BAPN腹腔注射能成功诱导小鼠主动脉夹层模型。

Objective To establish a mouse model of aortic dissection(AD) by intraperitoneal injection of angiotensin-Ⅱ(Ang-Ⅱ) combined with β-aminopropionitrile(BAPN). Methods Eighty three-week-old male C57 BL/6 J mice were randomly divided into the control group and another 7 experimental groups which include: Ang-Ⅱ group,0.1 g/kg BAPN group, 0.33 g/kg BAPN group, 0.67 g/kg BAPN group, Ang-Ⅱ+0.1 g/kg BAPN group, Ang-Ⅱ+0.33 g/kg BAPN group, and Ang-Ⅱ+0.67 g/kg BAPN group. The control group was intraperitoneally injected with 0.1 ml normal saline once every 8 h, the Ang-Ⅱ group with 4.0 mg/kg Ang-Ⅱ once every 8 h, 3 different doses of BAPN groups with 0.1, 0.33 and 0.67 g/kg BAPN once daily respectively, and the three combination treatment groups with0.1, 0.33, and 0.67 g/kg BAPN once daily on the basis of intraperitoneal 4.0 mg/kg Ang-Ⅱ once every 8 h. The blood pressure of the mice was detected and recorded by a rat tail manometer at the same time point for 14 days. Premature dead mice were subject to dissection and harvest of the aorta. After 14 days, the mice were sacrificed and the aorta was removed for pathological study. Results There was no significant difference in blood pressure between the control group and the three BAPN groups not given Ang-Ⅱ(P>0.05) but the blood pressure significant differed between the control group and the four groups given Ang-Ⅱ(P<0.05). The control group was free of AD formation and presented complete structure of the vessel walls by HE staining. In certain mice of the experimental groups, HE staining showed destructed elastic fibers, pseudo-cavity and inflammatory infiltration of vessel walls, suggesting formation of AD. In the 0.1 g/kg, 0.33 g/kg and 0.67 g/kg BAPN groups, the incidence of AD was 10%, 30% and 50%, respec-tively, gradually increasing along with higher BAPN doses. Part of mice in these three groups died of aortic rupture(n=0, 1, and 4, respectively). The incidence of AD in the Ang-Ⅱ group and the Ang-Ⅱ+ 0.1 g/kg BAPN group was lower(30% each), with the number of deaths being 1 and 0, respectively. The incidence of AD in Ang-Ⅱ+ 0.33 g/kg BAPN group and Ang-Ⅱ+0.67 g/kg BAPN group was 70% and 80%, respectively. Two mice in the Ang-Ⅱ+ 0.33 g/kg BAPN group and eight in the Ang-Ⅱ+0.67 g/kg BAPN group died of AD. The Ang-Ⅱ+ 0.33 g/kg BAPN group showed a high incidence but low mortalityof AD, which was in consistent with requirements for AD modeling in mice.Conclusion Intraperitoneal injection of Ang-Ⅱ combined with β-BAPN may successfully induce aortic dissection in mice.