Cardiac pacemaker and eventual action potential in contractile cells. Having cardiomyocytes connected via gap junctions allow all contractile cells of the heart to act in a coordinated fashion and contract as a unit. All the while being in sync with the pacemaker cells; this is the property that allows the pacemaker cells to control contraction in all other cardiomyocytes. Cells in the SA node spontaneously depolarize, ultimately resulting in contraction, approximately 100 times per minute. This native rate is constantly modified by the activity of sympathetic and parasympathetic nerve fibers via the autonomic nervous system, so that the average resting cardiac rate
Cardiac neural crest cells of differentiated cells such as neurons, glial cells, pigment-containing cells in skin, skeletal tissue cells in the head, and many more. Cardiac neural crest cells (CNCCs) are a type of neural crest cells that migrate to the circumpharyngeal ridge (an arc-shape ridge above the pharyngeal arches) and then into the 3rd, 4th and 6th pharyngeal arches and the cardiac outflow tract (OFT). They extend from the otic placodes (the structure in developing embryos that will later form the ears) to the third somites (clusters of mesoderm that will become skeletal muscle, vertebrae and dermis). The cardiac neural crest cells have