Mitochondrion (cardiomyocyte)

Mitochondria in cardiomyocytes are specialized double-membraned organelles responsible for generating the majority of cellular ATP through oxidative phosphorylation to meet the high energy demands of cardiac muscle contraction. They occupy approximately one-third of the cardiomyocyte’s volume and exist as several subpopulations based on location and function (interfibrillar, subsarcolemmal, perinuclear). In addition to energy production, they play key roles in calcium buffering, redox signaling, regulation of apoptosis, and adaptation to stress through dynamic processes such as fusion, fission, biogenesis, and mitophagy. Dysfunction of cardiac mitochondria contributes to a range of cardiovascular diseases, including ischemia–reperfusion injury, heart failure, and mitochondrial cardiomyopathies. Interventions targeting mitochondrial quality control, ROS production, and bioenergetic function are active areas of therapeutic investigation. This entry describes the organelle (not a discrete molecular target), highlights its major functions and pathophysiological roles in cardiomyocytes, and indicates why it is not cataloged as a "target" in the strict molecular/pharmacological sense.

Other names

Cardiac mitochondrionheart mitochondrioncardiomyocyte mitochondrioncardiac muscle mitochondrion

Drugs targeting mitochondrial function operate via diverse mechanisms including inhibition or modulation of components of the electron transport chain, modulation of the mitochondrial permeability transition pore to prevent cell death, antioxidant activity to scavenge reactive oxygen species or increase mitochondrial antioxidant defenses, and stimulation of mitochondrial biogenesis or mitophagy to restore function.