Distribution of M Cells in the Canine Ventricle

Abstract

Our results indicate that M cells reside throughout the deep subepicardial layers of the free wall of the canine left ventricle as well as in the deep subendocardial layers of the septum, papillary muscles, and trabeculae. The data also demonstrate prominent transmural as well as apicobasal gradients of phase 1 and phase 3 repolarization. These findings may have implications relative to our understanding of the electrocardiographic J wave, T wave, U wave, and long QTU intervals.