Table of Contents Author Guidelines Submit a Manuscript
Journal of Biomedicine and Biotechnology
Volume 2012, Article ID 732909, 8 pages
http://dx.doi.org/10.1155/2012/732909
Research Article

Desipramine Pretreatment Improves Sympathetic Remodeling and Ventricular Fibrillation Threshold after Myocardial Ischemia

1Department of Cardiology, Renmin Hospital of Wuhan University, Hubei Province, Wuhan 430060, China
2Department of Cardiology, Xiangyang Central Hospital, Hubei Province, Xiangyang 441000, China

Received 15 March 2012; Revised 6 May 2012; Accepted 6 May 2012

Academic Editor: Dobromir Dobrev

Copyright © 2012 Xiaolin Wu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Abnormal increase in sympathetic nerve sprouting was responsible for the ventricular arrhythmogenesis after myocardial infarction. This study investigated whether the norepinephrine transporter inhibitor, desipramine, can modulate sympathetic remodeling and ventricular fibrillation threshold (VFT) after myocardial ischemia-reperfusion. Rats were administered desipramine (0.8 mg/kg, IV) before or after myocardial ischemia. VFT, infarct size, tyrosine hydroxylase (TH) and growth-associated protein 43 (GAP43)-positive nerve fibers were measured after one week. The VFT of preischemic treatment group was 1 1 . 0 ± 2 . 6 5  V and significantly higher than that of control ischemic group ( 7 . 2 ± 1 . 3 0  V, 𝑃 < 0 . 0 5 ). Infarct size in the preischemic treatment group ( 2 3 . 3 ± 2 . 4 %) was significantly lower than that in the control ischemic group ( 3 0 . 8 ± 1 . 3 %, 𝑃 < 0 . 0 5 ) and the delayed application group ( 2 7 . 1 ± 2 . 6 %, 𝑃 < 0 . 0 5 ). The density of TH and GAP43-positive nerve fibers in the control ischemic group was significantly higher than that in the other three groups ( 𝑃 < 0 . 0 5 ). The density of nerve fibers improved after desipramine treatment. Moreover, there was a negative correlation between the VFT and both TH and GAP43-positive nerve fiber density in the infarct border zone ( 𝑃 < 0 . 0 5 ). Desipramine treatment before acute myocardial ischemia can decrease infarct size, improve sympathetic remodeling, and increase VFT and electrical stability of ischemic hearts. Desipramine appears to cause myocardial ischemic preconditioning.