Gain of function of Kir4.1 channel increases cell resistance to changes of potassium fluxes and cell volume evoked by ammonia and hypoosmotic stress.
Journal Title: Pharmacological Reports - Year 2010, Vol 62, Issue 6
Abstract
The Kir4.1 channel is an inward rectifying potassium channel involved in the control of potassium and water movement in mammalian cells. To evaluate independently the role of Kir4.1 alone and without interaction with other cellular effectors, we compared (86)Rb fluxes and cell volume in Kir4.1 transfected cells (Kir4.1(+)) with cells transfected with an empty vector (Kir4.1(-)). Transfection with Kir4.1 neither increased (86)Rb uptake nor (86)Rb efflux from cells in isotonic medium. Pretreatment with ammonia (5mM ammonium chloride) in isotonic medium produced a pronounced increase of (86)Rb uptake and a moderate decrease of cell volume in Kir4.1(-) but not in Kir4.1(+) cells. However, pretreatment evoked no change in (86)Rb efflux in either cell type. Hypotonic treatment (HT) markedly increased (86)Rb efflux in Kir4.1(-) cells and increased cell volume in both cell types. Although pretreatment with ammonia did not alter the effect of HT on (86)Rb efflux in either Kir4.1(+) or Kir4.1(-) cells, it potentiated the effect of hypotonic treatment in increasing cell volume in Kir4.1(-) cells. The results demonstrate that the presence of Kir4.1 in cells increases their resistance to alterations of potassium fluxes and/or cell volume imposed by ammonia and hypotonicity.
Authors and Affiliations
Marta Obara-Michlewska, Haiyan Jiang, Michael Aschner, Jan Albrecht
Keywords
Related Articles
- EP ID EP85282
- DOI -
- Views 100
- Downloads 0
Inflammatory lipid mediators in ischemic retinopathy.
Ischemic proliferative retinopathy develops in various retinal disorders, including retinal vein occlusion, diabetic retinopathy and retinopathy of prematurity. Ischemic retinopathy remains a common cause of visual impai...
Abstracts of the Third Conference on PROGRESS IN EPILEPTIC AND ANTIEPILETIC DRUGS.
Effect of neuroleptics on cytochrome P450 2C11 (CYP2C11) in rat liver.
The aim of the present study was to investigate the influence of classic and atypical neuroleptics on the activity of cytochrome P450 2C11 (CYP2C11), measured as a rate of testosterone 2α- and 16α-hydroxylation. The reac...
Effect of repeated co-treatment with imipramine and metyrapone on the behavioral reactivity of the central serotonin, dopamine and alpha(1)-adrenergic systems in rats.
The aim of present study was to examine the effect of repeated co-treatment with imipramine and metyrapone on the development of adaptive changes in the function of central serotonin 5-HT(1A) and 5-HT(2A), dopamine D(2/3...
Vascular prostaglandin synthesis: the early days.
Prostacyclin (PGI(2)) and thromboxane (TxA(2)) labile cyclooxygenase (COX) products via PGH(2) were identified in biological fluids by the ingenious application of the principle of parallel pharmacological assays develop...