ANATOMY

Detailed explanation-1: -Diastolic Depolarization is the Essence of Pacemaking Recent work in the atrioventricular node and Purkinje cells suggests that the mechanisms governing sino-atrial node automaticity are likely to be similar in all pacemaking tissues.

Detailed explanation-2: -Diastole describes the phase of the cardiac cycle during which blood from the atria of the heart are filling the ventricles. During this phase the ventricles are relaxed. Depolarization and repolarization are phases of an action potential.

Detailed explanation-3: -In mammals, cardiac electrical activity originates from specialized myocytes of the sinoatrial node (SAN) which generate spontaneous and rhythmic action potentials (AP). The unique functional aspect of this type of myocyte is the absence of a stable resting potential during diastole.