快速心房起搏诱导猪持续性房颤心房组织ACE2表达及替米沙坦干预的影响  

The expression of ACE2 in porcine atrial tissue with chronic atrial fibrillation induced by rapid atrial pacing and the effect of angiotensin receptor blocker on its expression

作　　者：李思召[1] 王志荣[2] 张超群[2] 徐晤[2] 张辉[2] 郑雯[2] 

机构地区：[1]丰县人民医院心内科,江苏丰县221700 [2]徐州医学院附属医院心内科,江苏徐州221002

出　　处：《徐州医学院学报》2011年第12期799-801,共3页Acta Academiae Medicinae Xuzhou

摘　　要：目的 探讨猪心房颤动（房颤）心房肌组织中血管紧张素转换酶2（ACE2）的表达和替米沙坦干预的作用.方法 18只健康小猪随机分为3组,分别为正常对照组（假手术组）、快速心房起搏组（RAP组）、替米沙坦干预组（起搏＋替米沙坦,ARB组）,每组各6头猪.对照组安置起搏器（AOO）但不行起搏刺激,其余各组安置起搏器,给予500次/min的快速右心房起搏2周,制成慢性房颤实验模型.各组均给予相同饲料喂养.替米沙坦（1.5 mg·kg^-1·d^-1）混于饲料中,并提前3天应用于ARB组;2周后处死所有实验猪,免疫组化染色方法 观察心房组织ACE2蛋白表达及定位;Western Blot检测心房组织ACE2的表达变化.结果 免疫组化染色可见：RAP组心房组织ACE2阳性染色较正常对照组明显减少,ARB干预组ACE2阳性染色较RAP组明显增加,接近正常对照组.与正常对照组比较,RAP组ACE2蛋白表达明显降低（P〈0.05）,替米沙坦干预组ACE2蛋白表达较RAP组明显增加（P〈0.05）.结论 房颤心房肌组织中ACE2表达下调,替米沙坦对房颤的效应可能与其上调ACE2有关.Objective In porcine atrial fibrillation （AF） models induced by two -week rapid right atrial pacing （RAP） and the effect of telmisartan, an angiotensin receptor- 1 blocker （ARB）, on the expression of ACE2. Methods 18 healthy pigs were randomly enrolled in control group （sham operation） , RAP group, ARB group （RAP ＋ Timisartan）. Sustained AF was induced by rapid right atrial pacing with 500 beats per minute for two weeks in each group except control group. Timisartan （ 1.5 mg·kg^ - 1 . d^ - 1 was administered orally for three days before rapid pacing and was continued for two weeks after operation. Transmural atrial free wall tissue samples were obtained and stored in liquid nitrogen for further study. ACE2 expresstion in atria was detected by immunobistocbemistry method. Western blot was used to test the expression of atrial ACE2 protein. Results Immunohistochemistry showed that ACE2 was mainly expressed in atrial cardiomyocytes and vascular endothelial cells. Positive staining of ACE2 in RAP group was obviously decreased than control group and ARB group. Compared with control group, the ACE2 protein expression was significantly decreased in RAP group （ P 〈 0.05 ）, and the expression of ACE2 was no significant change in ARB group （ P 〉 0.05 ）. Condusion These findings from this study indicate that ACE2 level may play an important role in the process of atrial fibrillation. The effect that timisartan inhibit AF incidence and shorten the duration of AF may be through upregulating the expression of ACE2.

关 键 词：心房颤动 血管紧张素转换酶2 血管紧张素受体阻断剂 猪 

分 类 号：R541.7[医药卫生—心血管疾病]