Altered right atrial excitation and propagation in connexin40 knockout mice.

ABSTRACT:

Background

Intercellular coupling via connexin40 (Cx40) gap junction channels is an important determinant of impulse propagation in the atria.

Methods and results

We studied the role of Cx40 in intra-atrial excitation and propagation in wild-type (Cx40(+/+)) and knockout (Cx40(-/-)) mice using high-resolution, dual-wavelength optical mapping. On ECG, the P wave was significantly prolonged in Cx40(-/-) mice (13.4+/-0.5 versus 11.4+/-0.3 ms in Cx40(+/+)). In Cx40(+/+) hearts, spontaneous right atrial (RA) activation showed a focal breakthrough at the junction of the right superior vena cava, sulcus terminalis, and RA free wall, corresponding to the location of the sinoatrial node. In contrast, Cx40(-/-) hearts displayed ectopic breakthrough sites at the base of the sulcus term

SUBMITTER: Bagwe S 

PROVIDER: S-EPMC2956435 | biostudies-literature | 2005 Oct

REPOSITORIES: biostudies-literature