Effects of metoprolol on electrophysiology of ischemic and anoxic myocardium in diabetic rats.
- Author:
Hong-feng JIN
1
;
Wen-ping ZENG
;
Fa-rong SHEN
;
Zhi-jun WANG
;
Lang HE
;
Guo-jian SUN
;
Jian-ming CHEN
;
Cheng ZHONG
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Diabetes Mellitus, Experimental; physiopathology; Heart; drug effects; physiopathology; Male; Metoprolol; pharmacology; Myocardial Ischemia; physiopathology; Nerve Growth Factor; blood; Rats; Rats, Sprague-Dawley; Sympathectomy
- From: Journal of Zhejiang University. Medical sciences 2011;40(6):653-658
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo investigate the effects of metoprolol on electrophysiology of ischemic and anoxic myocardium in diabetic rats.
METHODSForty Sprague-Dawley (SD) rats were divided into 4 groups: diabetes group; diabetes and ablation of left sympathetic nerve group; diabetes and metoprolol group and sham group. The diabetes model was induced by intraperitoneal injection of streptozotocin (STZ, 60 mg/kg). The ventricular diastolic effective threshold (DET), effective refractive period (ERP), and Ventricular fibrillation threshold (VFT) were measured. The serum concentration of nerve growth factor (NGF) was measured.
RESULTSMetoprolol increased DET of ischemic and anoxic myocardium in diabetic rats. The ablation of the left sympathetic nerve increased VFT of diabetic rats. VFT in metoprolo group was significantly increased compared to diabetes group after ischemia. The concentrations of NGF in diabetic group and metoprolol group were higher than those in sham group. There were no difference in NGF levels between ablation of left sympathetic nerve group and sham group.
CONCLUSIONThe remodeling of sympathetic nerve affects the electrophysiology of ischemic myocardium of diabetic rats. Metoprolol can increase the VFT and decrease the excitation threshold of the ischemic myocardium in diabetic rats.
