Characteristics of Atrial Substrates for Atrial Tachyarrhythmias Induced in Aged and Hypercholesterolemic Rabbits

PACE - Pacing and Clinical Electrophysiology - Tập 35 Số 5 - Trang 544-552 - 2012
Kun‐Tai Lee1,2, Chong‐Chao Hsieh1, Wei‐Chung Tsai1, Paul Wei-Hua Tang1, I-Hsin Liu1, Chee‐Yin Chai2,3, Ming‐Tsang Wu1,2, Wen‐Ter Lai1,2
1Cardiovascular Center, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
2Department of Internal Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
3Department of Pathology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan

Tóm tắt

Background: Old age and dyslipidemia increase the occurrence of atrial tachyarrhythmias (ATR). This study investigated the effect of age and hypercholesterolemia on the atrial substrates for ATR. Methods: Five 3‐year‐old rabbits fed standard chow were categorized into an old‐age group, five 3‐month‐old rabbits fed high cholesterol chow were used as a hypercholesterolemia group, and five 3‐month‐old rabbits fed standard chow were controls. Effective refractory period, atrial vulnerability to ATR, expressions of connexin40 (Cx40) and connexin43 (Cx43), phosphorylated c‐Jun N‐terminal Kinase (P‐JNK), and degree of fibrosis in the right (RA) and left (LA) atria were compared. Results: Old‐age and hypercholesterolemia rabbits were more vulnerable to ATR than the controls (18,628 ± 13,981 ms and 30,157 ± 39,548 ms vs 639 ± 325 ms, P < 0.05). Old‐age rabbits had significantly decreased Cx40 expression in both atria (3.9‐fold decrease in RA, P < 0.01 and 4.8‐fold in LA, P < 0.01) and significantly decreased Cx43 in RA (14‐fold, P < 0.01). Hypercholesterolemia rabbits had significantly decreased Cx40 expression in both atrial (18‐fold decrease in RA, P < 0.01 and 17‐fold in LA, P < 0.01) and significantly increased Cx43 expression in LA (five‐fold increase, P < 0.01). Hypercholesterolemia, but not old‐age rabbits, had greater expression of P‐JNK in both atria (1.8‐fold in RA and 2.3‐fold in LA, P < 0.01). There were no significant group differences in ERP or degree of atrial fibrosis in both atria. Conclusions: ATR is more easily induced in the atria of old‐age and hypercholesterolemia rabbits than younger rabbits with normal cholesterol levels. The age and hypercholesterolemia induced changes in gap junctions expression may have partially contributed to the higher atrial vulnerability to ATR. (PACE 2012;1–9)

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Tài liệu tham khảo

10.1016/S0002-9149(98)00583-9

10.1016/j.ahj.2008.10.009

10.1016/j.pcad.2005.06.014

10.1161/01.CIR.0000157153.30978.67

10.1161/CIRCEP.109.859116

Benjamin EJ, 1994, Independent risk factors for atrial fibrillation in a population‐based cohort. The Framingham Heart Study, JAMA, 271, 33, 10.1001/jama.1994.03510350050036

10.1253/circj.72.909

10.1161/01.RES.0000072999.51484.92

10.1111/j.1540-8167.2006.00528.x

10.1159/000259899

10.1093/cvr/cvp203

10.1016/S0008-6363(01)00324-8

10.1016/j.cardiores.2003.12.007

10.1161/01.CIR.97.7.686

10.1016/j.yjmcc.2003.10.006

10.1111/j.1540-8167.1998.tb00941.x

10.1016/S0735-1097(01)01710-7

10.1016/S0008-6363(00)00026-2

10.1161/01.CIR.99.11.1508

10.1016/S0960-9822(98)70114-9

10.1161/CIRCULATIONAHA.104.527325

10.1016/0014-4827(91)90457-6

10.1016/S0140-6736(97)10049-6

10.1161/01.RES.0000035854.11082.01

10.1038/labinvest.3700324

10.1080/08941930802713035

10.1159/000159198

10.1161/01.CIR.96.4.1180

10.1016/S1001-9294(09)60008-0

10.1016/j.yjmcc.2009.09.001

10.1046/j.1540-8167.2002.00801.x

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PACE - Pacing and Clinical Electrophysiology

Tập 35 Số 5

544-552

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