ATP-regulated K+ channel

ATP-sensitive K+ channel ATP-regulated K+ channel Kaxp channel SURx/Kir6.x channel... 

Fernandez-Veledo, S., Casado, V., Norman, R.I.. Casado, F.J., lluis, C., Franco, R., and Pastor-Ariglada, M. (2004) ATP-sensitive K channels regulate the concentrative adenosine transporter CNT2 following activation hy A] adenosine receptors. Molecular and Cellular Biology, 24 (7), 2710-2719. 

New interest has focused on the possibility that ATP-regulated K+ (K tp) channels might be involved in the membrane response to metabolic inhibition (Standen et al., 1989 Daut et al., 1990). These channels are blocked by ATP and activated by nucleoside diphosphates, and thus would be expected to increase their conductance as [ADP]/[ATP] increases, leading to hyperpolarization. This suggests an attractive hy-... 

Hansen SB, TaoX, MacKinnon R (2011) Structural basis of P1P2 activation of the classical inward rectifier channel Kir2.2. Nature (Lond) 477 495 98 Hibino H, Inanobe A, Furutani K, Murakami S, Findlay 1, Karachi Y (2010) Inwardly rectifying potassium channels their structure, function, and physiological roles. Physiol Rev 90 291-366 Ho K, Nichols CG, Lederer WJ, Lytton J, VassUev PM, Kanazirska MV, Hebert SC (1993) Qoning and expression of an inwardly rectifying ATP-regulated potassium channel. Nature (Lond) 362 31-38... 

Within seconds of an ischemic insult, normal brain electrical activity ceases, as a result of the activation of membrane K+ channels and widespread neuronal hyperpolarization [1]. The hyperpolarization may be due to opening of K+ channels responding to acute changes in local concentrations of ATP, H+ or Ca2+, or it may reflect altered nonheme metalloprotein association with and regulation of specific K+ channels [2]. This response, presumably protective, however fails to preserve high-energy phosphate levels in tissue as concentrations of phospho-creatine (PCr) and ATP fall within minutes after ischemia... 

For the internalisation of metals, many examples exist for which transport may be coupled to an energy-dependent process, of which only a few are described here. For example, the well-studied (e.g. [276]) Na+/K+ channel transports 3Na+ out and 2K+ in for each ATP molecule that is hydrolysed [242]. Mg2+ influx (but likely not efflux) is highly regulated in eukaryotes [277]. ATPases have been implicated in certain cases of Fe [278] or Zn [90] uptake by phytoplankton. Finally, although Cd internalisation by a polychaete appeared to be energy independent, accumulation was increased rather than decreased in the presence of ATPase inhibitors, suggesting that the efflux system might depend upon ATP synthesis [279]. 

ATP-dependent ABC transporter family. However, it is atypical because it also contains a regulated chloride channel) In secretory epithelia of intestines, pancreas, lungs, sweat glands, and kidneys Cl enters epithelial cells through their basolateral surfaces using an Na+ + K+ + 2 Cl cotransporter and exits the cells through their apical surfaces using the CFTR channel. Absorptive epithelia also contain both the cotransporter and the CFTR channel, but Cl flows into the cells from the exterior surface, and the distribution of the cotransporter and CFTR between basolateral and apical surfaces is opposite to that in secretory cells.1... 

Some are inhibited by ATP 173 l7 lb and others by eicosanoids475 or inositol hexaphosphate.476 Some of the ATP-sensitive channels contain an ABC transporter subunit and are binding sites for sulfonylureas and other drugs. See discussion on p. 421. A number of human disorders in Kir channels have been identified.468 Tire human Kir channels participate in regulation of resting membrane potentials in K+ homeostasis, control of heart rate, and hormone secretion.468 A third group of K+ channels are dimeric, but each subunit contains two tandem P regions and 4-8 transmembrane helices.455... 

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