Impulse propagation in synthetic strands of neonatal cardiac myocytes with genetically reduced levels of connexin43.

ABSTRACT: Connexin43 (Cx43) is a major determinant of the electrical properties of the myocardium. Closure of gap junctions causes rapid slowing of propagation velocity (theta), but the precise effect of a reduction in Cx43 levels due to genetic manipulation has only partially been clarified. In this study, morphological and electrical properties of synthetic strands of cultured neonatal ventricular myocytes from Cx43+/+ (wild type, WT) and Cx+/- (heterozygote, HZ) mice were compared. Quantitative immunofluorescence analysis of Cx43 demonstrated a 43% reduction of Cx43 expression in the HZ versus WT mice. Cell dimensions, connectivity, and alignment were independent of genotype. Measurement of electrical properties by microelectrodes and optical mapping showed no differences in action potential ampl

SUBMITTER: Thomas SP 

PROVIDER: S-EPMC2242733 | biostudies-literature | 2003 Jun

REPOSITORIES: biostudies-literature