Growing evidence exists that ATP-sensitive mitochondrial potassium channels (MitoKATP channel) are a major contributor to the cardiac protection against ischemia. Given the importance of mitochondria in the cardiac cell, we tested whether the potent and specific opener of the MitoKATP channel diazoxide attenuates the lethal injury associated with Ca2+overload. The specific aims of this study we...

Lethal injury to the heart can be dramatically blunted by brief periods of prior ischemia.1 Such an endogenous cardioprotective mechanism, known as ischemic preconditioning (IPC), exists in all species examined to date, including humans.2 IPC occurs in a biphasic pattern of myocardial protection: an early phase (classic IPC), which develops immediately and lasts approximately 2 hours after the ...

Perfusion of the heart with bradykinin triggers cellular signaling events that ultimately cause opening of mitochondrial ATP-sensitive K+ (mitoKATP) channels, increased H2O2 production, inhibition of the mitochondrial permeability transition (MPT), and cardioprotection. We hypothesized that the interaction of bradykinin with its receptor induces the assembly of a caveolar signaling platform (si...

The mitochondrial KATP channel (mitoKATP) is hypothesized to be the receptor for the cardioprotective effects of K+ channel openers (KCO) and for the blocking of cardioprotection by glyburide and 5-hydroxydecanoate (5-HD). Studies on glyburide have indicated that this drug is inactive in isolated mitochondria. No studies of the effects of 5-HD on isolated mitochondria have been reported. This p...

OPENING of the ATP-sensitive K (KATP) channel mediates the cardioprotective effect induced by pathophysiological stressors such as ischemic preconditioning (IPC) (15, 29), heat shock (19), and pharmacological agents, including adenosine (5), ACh (26), opioids (12), monophosphoryl lipid A (31), phosphodiesterase 5A (PDE5A) inhibitors (24, 27), and mTOR inhibitor, rapamycin (20). In addition, dir...

THE FINE STUDY by Jiang et al. (8) in this issue of the American Journal of Physiology Heart and Circulatory Physiology is an important milestone in the ongoing studies on the role of the mitochondrial ATP-sensitive K (mitoKATP) channels in myocardial ischemia. It is not particularly surprising that this channel exists in human cardiac myocytes, because most proteins are highly conserved in mit...

Garlid AO, Jaburek M, Jacobs JP, Garlid KD. Mitochondrial reactive oxygen species: which ROS signals cardioprotection? Am J Physiol Heart Circ Physiol 305: H960–H968, 2013. First published August 2, 2013; doi:10.1152/ajpheart.00858.2012.—Mitochondria are the major effectors of cardioprotection by procedures that open the mitochondrial ATP-sensitive potassium channel (mitoKATP), including ischem...

The mitochondrial ATP-dependent K channel (mitoKATP) has been shown to play a role in cellular protection against apoptosis, or programmed cell death. This channel has been identified and characterized in a number of cell and tissue types but to date the possible existence of mitoKATP in osteoblastic cells has not been investigated. The aim of this investigation was to establish whether the mit...

OBJECTIVE Ischemic preconditioning confers cardioprotection in early and delayed phases. We investigated the delayed window of pharmacological and ischemic preconditioning in human myocardium, and the involvement of mitoKATP, PKC and p38MAPK. METHODS These studies were carried out using human right atrial tissue in a cell necrosis model. The tissue was obtained from patients undergoing corona...

ATP-sensitive K(+) (KATP) channels are present on the sarcolemma (sarcKATP channels) and mitochondria (mitoKATP channels) of cardiac myocytes. Amiodarone, a class III antiarrhythmic drug, reduces sudden cardiac death in patients with organic heart disease. The objective of the present study was to investigate the effects of amiodarone on sarcKATP and mitoKATP channels. Single sarcKATP channel c...