Distinct shear-induced Ca signaling in the left and right atrial myocytes: Role of P2 receptor context.

Atrial myocytes are continuously exposed to shear stress during cardiac cycles. Previous reports have shown that shear stress induces two different types of global Ca signaling in atrial myocytes-longitudinal Ca waves (L-waves) and action potential-involved transverse waves (T-waves), and suggested an underlying role of the autocrine activation of P2 receptors. We explored the correlations between ATP release and Ca wave generation in atrial myocytes and investigated why the cells develop two Ca-wave types during the same shear force.