Distribution of t-tubule density in atrial and ventricular cells from tissue sections.

<p>A) Frequency distributions of, respectively, atrial (i) and ventricular (ii) myocyte t-tubule density. B) Correlation of t-tubule density with short axis diameter. (i) Data shown separately for atrial cells with ‘low TTD’ (open circles, <i>n</i> = 17), in atrial cells with ‘high TTD’ (grey-filled diamonds, <i>n</i> = 5) and in ventricular cells (black-filled squares, <i>n</i> = 24). Spearman’s correlation coefficient is shown (<i>n</i> = 46). TTD was correlated with short axis diameter for both atrial cells (r = 0.6025, P = 0.0030, <i>n</i> = 22) and ventricular cells (r = 0.4887, P = 0.0154, <i>n</i> = 24). (ii) Data shown as mean±SEM for each cell type. ** P<0.01, *** P<0.0001 one-way ANOVA with Bonferroni post-test for TTD. ## P<0.01, ### P<0.0001 one-way ANOVA with Bonferroni post-test for short axis diameter. Data were obtained from atrial and ventricular sections obtained from 3 pigs for either cell type.