Patterning of coronary arteries in wildtype and connexin43 knockout mice.

Abnormal patterning of coronary arteries (CAs) is a clinically significant problem, and as yet, few animal models have been systematically investigated for coronary patterning defects. Here we characterized coronary artery (CA) insertion and branching patterns of the proximal coronary stems in the hearts of wildtype and heterozygous connexin43 knockout (Cx43alpha1 KO) mice. This study entailed the use of high-resolution micro CT imaging for three-dimensional coronary reconstructions.

Connexin43 deficiency causes dysregulation of coronary vasculogenesis.

The connexin43 knockout (Cx43alpha1 KO) mouse dies at birth from outflow obstruction associated with infundibular pouches. To elucidate the origin of the infundibular pouches, we used microarray analysis to investigate gene expression changes in the pouch tissue. We found elevated expression of many genes encoding markers for vascular smooth muscle (VSM), endothelial cells, and fibroblasts, cell types that are epicardially derived and essential for coronary vasculogenesis.