title: Risk of ventricular arrhythmias after myocardial infarction with diabetes associated with sympathetic neural remodeling in rabbits.
abstract: BACKGROUND
  Abnormal sympathetic innervation underlies both long-term hyperglycemia and myocardial infarction (MI). The incidence of ventricular arrhythmias (VAs) after MI is higher in diabetic than in nondiabetic patients. However, the exact mechanism remains unclear. In this study, we aimed to explore sympathetic neural remodeling after MI in diabetic rabbits and its relationship with VAs.
  
  
  METHODS
  Rabbits were randomly assigned to 4 groups: control, diabetes mellitus (DM), MI and diabetic myocardial infarction (DI). After electrophysiological experiments in vivo, immunohistochemistry and real-time RT-PCR were used to measure sympathetic innervations. To test the function of sympathetic nerve fibers, norepinephrine levels were measured by high-performance liquid chromatography.
  
  
  RESULTS
  The corrected QT interval and QT dispersion were significantly more prolonged with DI than other conditions. The density of tyrosine hydroxylase-positive fibers and corresponding mRNA abundance was significantly higher with DI than with DM and under control conditions, but was lower than with the MI group. Moreover, the distribution and structure of regenerated nerve was heterogeneous in DI rabbits. Norepinephrine content was higher in the DI group, and accompanied by an increased quantity of tyrosine hydroxylase-positive fibers.
  
  
  CONCLUSIONS
  MI results in sympathetic neural remodeling in diabetic rabbits, which may be responsible in part for the increased occurrence of VAs.
authors.affiliation: School of Medicine, Shandong University, Jinan, PR China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Wang
authors.forename: Yong-Li
authors.initials: YL
authors.lastname: Xuan
authors.forename: He-Sheng
authors.initials: HS
authors.lastname: Hu
authors.forename: Xiao-Lu
authors.initials: XL
authors.lastname: Li
authors.forename: Mei
authors.initials: M
authors.lastname: Xue
authors.forename: Wen-Juan
authors.initials: WJ
authors.lastname: Cheng
authors.forename: Fei
authors.initials: F
authors.lastname: Suo
authors.forename: Su-Hua
authors.initials: SH
authors.lastname: Yan
mesh_terms: D000818:Animals; D001145:Arrhythmias, Cardiac / Q000209:etiology / Q000473:pathology*; D001342:Autonomic Nervous System Diseases / Q000209:etiology / Q000473:pathology*; D003921:Diabetes Mellitus, Experimental / Q000150:complications / Q000473:pathology; D058065:Diabetic Cardiomyopathies / Q000209:etiology / Q000473:pathology*; D003929:Diabetic Neuropathies / Q000209:etiology / Q000473:pathology*; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D006352:Heart Ventricles / Q000294:innervation*; D007150:Immunohistochemistry; D009203:Myocardial Infarction / Q000209:etiology / Q000473:pathology*; D009206:Myocardium / Q000737:chemistry; D009638:Norepinephrine / Q000378:metabolism; D011817:Rabbits; D011897:Random Allocation; D060888:Real-Time Polymerase Chain Reaction; D012307:Risk Factors; D020257:Ventricular Remodeling / Q000502:physiology
chemical_list: D009638:Norepinephrine