Preventive Effects of the Angiotensin-II Receptor Blocker on Atrial Remodeling in an Ischemic Heart Failure Model of Rats.
10.4070/kcj.2013.43.10.686
- Author:
Namsik YOON
1
;
Kye Hun KIM
;
Keun Ho PARK
;
Doo Sun SIM
;
Hyun Ju YOUN
;
Young Joon HONG
;
Hyung Wook PARK
;
Ju Han KIM
;
Youngkeun AHN
;
Myung Ho JEONG
;
Jeong Gwan CHO
;
Jong Chun PARK
Author Information
1. Department of Cardiology, Chonnam National University Hospital, Gwangju, Korea. jgcho@unitel.co.kr
- Publication Type:Original Article
- Keywords:
Angiotensin-II receptor blocker;
Atrial remodeling;
Atrial fibrillation
- MeSH:
Animals;
Angiotensin Receptor Antagonists*;
Atrial Fibrillation;
Azo Compounds;
Blotting, Western;
Connexin 43;
Coronary Vessels;
Echocardiography;
Eosine Yellowish-(YS);
Fibrosis;
Heart Failure*;
Heart Ventricles;
Heart;
Ligation;
Losartan;
Male;
Methyl Green;
Rats*;
Rats, Sprague-Dawley;
Stroke Volume
- From:Korean Circulation Journal
2013;43(10):686-693
- CountryRepublic of Korea
- Language:English
-
Abstract:
BACKGROUND AND OBJECTIVES: It is widely known that angiotensin-II receptor blockers (ARBs) have reverse remodeling effects in atrium. Although atrial fibrillation is frequent in ischemic heart failure clinically, experiments to demonstrate ARB's effects on atrial remodeling in a heart failure model are rare. MATERIALS AND METHODS: A heart failure model and a sham-operated group were formed in 25 Sprague-Dawley male rats of roughly 260 g in weight. Ischemic heart failure models were obtained via ligation of the left anterior descending coronary artery. In the ARB group, 30 mg/kg of losartan was administrated over a day for 4 weeks. Echocardiography was performed to measure left ventricle ejection fraction and left atrial diameter (LAD) at the baseline and 4 weeks after the operation. 4 weeks later, histologic and immunohistochemical evaluation were performed. RESULTS: Groups were divided into the sham group, heart failure group, and heart failure-ARB group. We maintained 5 rats in each group for 4 weeks after operation. The decrease of left ventricular ejection fraction in the heart failure-ARB group was less than that in the heart failure group (p=0.023). The increase of LAD in the heart failure-ARB group was less than that in the heart failure group (p=0.025). Masson's trichrome stain revealed less fibrosis in the heart failure-ARB group. Immunohistochemical stain and western blot for connexin 43 showed less expression in the heart failure-ARB group. CONCLUSION: In the ischemic heart failure model of rats, structurally and histologically, the ARB, losartan, has atrial reverse-remodeling effects. However, electrically, its role as an electrical stabilizer should be studied further.
