INVESTIGADORES
PERAL Maria De Los Angeles
congresos y reuniones científicas
Título:
A MURINE MODEL OF INDUCIBLE VENTRICULAR TACHYCARDIA FOR TRANSGENIC STUDIES
Autor/es:
CERVANTES DO.; HUSSAIN W.; TREO EF; PERAL DE BRUNO M;; PETERS NS; WIT AL
Lugar:
New Orleans, Louisiana, USA,
Reunión:
Congreso; 26va Reunión Científica de la Heart Rhythm Society (ex NASPE- North American Society of Pacing and Electrophysiology) en New Orleans, Louisiana, USA; 2005
Institución organizadora:
North American Society of Pacing and Electrophysiology
Resumen:
Background: A canine model of myocardial infarction (MI) clearly demonstrated the impact of gap-junctional pattern on impulse conduction and arrhythmias involving reentry in the healing epicardial border zone. In large species the arrhythmias following ischemia and infarction are relatively well characterized, but this is not he case for small animals. Since mouse hearts are clearly capable of initiating arrhythmias, there is considerable interest in defining whether the mouse is an appropriate model to explore arrhythmia mechanisms. Method: We monitored inducibility of ventricular tachycardia (VT) in mice in the absence (Sham-mice, n=16) or presence (MI-mice, n=46) of healing MI using programmed stimulation protocols 3 days after ligation of the left anterior descending artery. Infarct size (n=24) was measured using the tetrazolium method and calculated as a percentage of total LV volume. 3 hearts of MI-mice without inducible VT were sequentially sectioned, and 10 um sections every 100um were examined for standard histology and connexin43 (Cx43) immunohistochemistry. Results: There was significant difference in the number of MI-mice (21, 46%) versus Sham-mice (1, 6%) that exhibited VT. Mean infarct size was The relationship between VT inducibility and infarct size Standard histology and immunohistochemistry in the 3 hearts studied revealed the presence of infarction with clear epicardial and endocardial rims of surviving tissue. There was redistribution of Cx43 labeling to the lateral cell membrane in all areas overlying and immediately adjacent to infarcts, and the pattern returned to normal before the epicardial surface of the hearts.Conclusion: MI-mice exhibit enhanced arrhythmogenesis in the setting of healing MI 3 days after ligation of the left anterior descending artery in which there is a surviving epicardial border zone showing gap junction