Irbesartan prevents myocardial remodeling in experimental thyrotoxic cardiomyopathy

Endocrine Journal

Bo Gwang Choi²  Sang Soo Kim²  Ji Hyun Kang²  Seong Man Kim⁴  Jee-Yeon Kim¹  Bo Hyun Kim²  Seong-Jang Kim³  Yong Ki Kim⁵  Kyoung Im Cho⁴  Yun Kyung Jeon²  In Joo Kim² 

[1] Department of Pathology, Pusan National University School of Medicine, Busan 602-739, Korea;Department of Internal Medicine, Pusan National University School of Medicine, Busan 602-739, Korea;Department of Nuclear Medicine, Pusan National University School of Medicine, Busan 602-739, Korea;Department of Internal Medicine, Maryknoll Medical Center, Busan 600-730, Korea;Kim Yong Ki Internal Medicine Clinic, Busan 602-011, Korea

关键词: Cardiomyopathy;    Heart failure;    Thyrotoxicosis;    Renin-angiotensin system;    Echocardiography;   

DOI  :  10.1507/endocrj.EJ12-0111

学科分类：内分泌与代谢学

来源: Japan Endocrine Society

【 摘 要 】

References(37)This study evaluated the effects of irbesartan and propranolol on thyroid hormone (TH)-induced cardiac functional and structural remodeling. A rat model of thyrotoxicosis was established by daily intraperitoneal injections of L-thyroxine (T4, 100 μg/kg) for 4 weeks.Forty Sprague-Dawley rats were randomly divided into four groups (n = 10 each): control group, T4 group (T4 alone), T4 plus irbesartan group (T4-Irb, 30 mg/kg), and T4 plus propranolol group (T4-Pro, 0.5mg/mL of drinking water).Cardiac chamber size and functional parameters were measured by echocardiography and cardiomyocyte diameter.Heart rate (HR) and cardiac fibrosis were determined.T4 alone showed significantly increased HR and cardiomyocyte width (25.0 ± 1.77 vs. 18.8 ± 0.84 μm, P long; -16.0 ± 6.27 vs. -22.7 ± 5.19 %, P 4 alone, T4-Irb showed significantly improved LV Slong (-21.4 ± 1.84 vs. -16.0 ± 6.27 %, P =0.017) and reduced cardiomyocyte width (21.0 ± 1.0 vs. 25.0 ± 1.77 μm, P =0.002) with comparable HR (458.4 ± 24.3 vs. 486.6 ± 30.1 bpm, P = 0.086).However, T4-Pro showed significantly reduced HR with improved LV Slong without alteration of cardiomyocyte width and fibrosis compared with T4 alone.In conclusion, renin-angiotensin system (RAS) blocking by irbesartan could significantly attenuate TH-induced cardiac structural and functional remodeling.However, HR reduction by propranolol could not alternate structural remodeling, which may implicate the RAS as having an important role in thyrotoxic cardiomyopathy beyond tachycardia.

【 授权许可】

Unknown