title: Slow conduction and gap junction remodeling in murine ventricle after chronic alcohol ingestion.
abstract: BACKGROUND
  Long-term heavy alcohol drinkers are prone to the development of cardiac arrhythmia. To understand the mechanisms, we evaluated the cardiac structural and electrophysiological changes in mice chronically drinking excessive alcohol.
  
  
  RESULTS
  Male C57BL/6J mice were given 36% alcohol in the drinking water. Those given blank water were used as control. Twelve weeks later, the phenotypic characteristics of the heart, including gap junctions and electrical properties were examined. In the alcohol group the ventricles contained a smaller size of cardiomyocytes and a higher density of capillary networks, compared to the control. Western blots showed that, after drinking alcohol, the content of connexin43 (Cx43) protein in the left ventricle was increased by 18% (p < 0.05). Consistently, immunoconfocal microscopy demonstrated that Cx43 gap junctions were up-regulated in the alcohol group with a disorganized distribution, compared to the control. Optical mapping showed that the alcohol group had a reduced conduction velocity (40 ± 18 vs 60 ± 7 cm/sec, p < 0.05) and a higher incidence of ventricular tachyarrhythmia (62% vs 30%, p < 0.05).
  
  
  CONCLUSIONS
  Long-term excessive alcohol intake resulted in extensive cardiac remodeling, including changes in expression and distribution of gap junctions, growth of capillary network, reduction of cardiomyocyte size, and decrease of myocardial conduction.
authors.affiliation: Departments of Internal Medicine and Medical Research, Mackay Memorial Hospital, Mackay Medical College, New Taipei City, Taiwan.
authors.forename: Yu-Jun
authors.initials: YJ
authors.lastname: Lai
authors.forename: Chung-Lieh
authors.initials: CL
authors.lastname: Hung
authors.forename: Ray-Ching
authors.initials: RC
authors.lastname: Hong
authors.forename: Ya-Ming
authors.initials: YM
authors.lastname: Tseng
authors.forename: Cheng-I
authors.initials: CI
authors.lastname: Lin
authors.forename: Yu-Shien
authors.initials: YS
authors.lastname: Ko
authors.forename: Cheng-Ho
authors.initials: CH
authors.lastname: Tsai
authors.forename: Hung-I
authors.initials: HI
authors.lastname: Yeh
mesh_terms: D000428:Alcohol Drinking / Q000473:pathology* / Q000503:physiopathology*; D000818:Animals; D001145:Arrhythmias, Cardiac / Q000139:chemically induced* / Q000473:pathology / Q000503:physiopathology; D018031:Connexin 43 / Q000187:drug effects / Q000378:metabolism; D000431:Ethanol / Q000633:toxicity; D017629:Gap Junctions / Q000187:drug effects / Q000473:pathology*; D006329:Heart Conduction System / Q000187:drug effects / Q000503:physiopathology; D006352:Heart Ventricles / Q000187:drug effects / Q000473:pathology* / Q000503:physiopathology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D032383:Myocytes, Cardiac / Q000187:drug effects / Q000473:pathology / Q000502:physiology
chemical_list: D018031:Connexin 43; D000431:Ethanol