Biochemistry and physiology of cardiac muscle

The heart is composed of muscle cells (cardiomyocytes) that account for most of the heart mass and generate its pumping force. Other cell types (fibroblasts, vascular endothelial cells, vascular smooth muscle cells, immune cells) and the extracellular matrix also play key roles in cardiac function, in both health and disease. Excitation –contraction coupling links the electrical activation of cardiomyocytes to cellular contraction. Calcium is a key second messenger in this process; its entry into the cell triggers further calcium release from the sarcoplasmic reticulum, which then activates the contractile machinery.
Source: Medicine - Category: Internal Medicine Authors: Tags: The normal heart Source Type: research