Mitochondrial ATP-sensitive potassium channel (mitoKATP) (mitoKATP)

The Mitochondrial ATP-sensitive potassium channel (mitoKATP) is a key regulator of mitochondrial physiology located within the inner mitochondrial membrane (Paggio et al., 2019, Nature). It functions by modulating the influx of potassium ions into the mitochondrial matrix in response to the cellular ATP/ADP ratio, thereby maintaining mitochondrial volume homeostasis and regulating the mitochondrial membrane potential (O'Rourke, 2004, Physiological Reviews). This activity is crucial for controlling the production of reactive oxygen species and preventing the opening of the mitochondrial permeability transition pore, which protects cells from apoptosis and necrosis during metabolic stress (Szabo et al., 2021, Physiological Reviews). Pharmacological activation of mitoKATP is a well-established mechanism for ischemic preconditioning, offering significant protection against ischemia-reperfusion injury in cardiac and neuronal tissues (Garlid et al., 1997, Circulation Research). Recent molecular studies have identified the channel as a complex comprising the pore-forming subunit CCDC51 (MITOK) and the regulatory subunit ABCB8 (MITOSUR) (Paggio et al., 2019, Nature). Despite its therapeutic potential for treating myocardial infarction and stroke, the development of clinical candidates is complicated by the need for selectivity over plasma membrane KATP channels to avoid systemic side effects like hypotension (Foster et al., 2012, Journal of Cardiovascular Pharmacology).

Other names

Mitochondrial ATP-regulated potassium channelmitoKATP channelMitochondrial KATP channelMITOK/MITOSUR complex

The mechanism of action for drugs targeting the mitochondrial ATP-sensitive potassium channel involves the modulation of potassium conductance across the inner mitochondrial membrane. Openers, such as diazoxide, increase K+ influx, which leads to a slight depolarization of the mitochondrial membrane potential and a reduction in mitochondrial calcium overload, thereby preventing the opening of the mitochondrial permeability transition pore (mPTP) during reperfusion (Garlid & Halestrap, 2012, Journal of Molecular and Cellular Cardiology). Blockers, such as 5-hydroxydecanoate, are used to inhibit these effects and are primarily utilized in research to confirm the involvement of the channel in cytoprotective pathways (O'Rourke, 2004, Physiological Reviews).