title: Role of cholesterol in the maintenance of endplate electrogenesis in rat diaphragm.
abstract: Methyl-β-cyclodextrin (0.1 mM) reduced resting potential of muscle fibers and abolished local endplate membrane hyperpolarization in rat diaphragm. This effect was associated with selective reduction of electrogenic activity of α2-isoform of Na,K-ATPase without changes in the level of intracellular acetylcholine. Experiments with cholesterol marker filipin showed that methyl-β-cyclodextrin in this dose induced cholesterol translocation from lipid rafts to liquid phase of the membrane without its release into extracellular space. This modification of lipid rafts by methyl-β-cyclodextrin presumably impaired the mechanism maintaining electrogenesis in endplates mediated by modulation of Na,K-ATPase by non-quantum acetylcholine. Cholesterol can serve as a molecular component of this mechanism.
authors.affiliation: Department of General Physiology, St. Petersburg State University, St. Petersburg, Russia.
authors.forename: V V
authors.initials: VV
authors.lastname: Kravtsova
authors.forename: A M
authors.initials: AM
authors.lastname: Petrov
authors.forename: A N
authors.initials: AN
authors.lastname: Vasil'ev
authors.forename: A L
authors.initials: AL
authors.lastname: Zefirov
authors.forename: I I
authors.initials: II
authors.lastname: Krivoi
mesh_terms: D000109:Acetylcholine / Q000378:metabolism; D000818:Animals; D002784:Cholesterol / Q000378:metabolism*; D003964:Diaphragm / Q000187:drug effects* / Q000378:metabolism*; D008297:Male; D021962:Membrane Microdomains / Q000187:drug effects / Q000378:metabolism; D020033:Protein Isoforms / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D047392:beta-Cyclodextrins / Q000494:pharmacology*
chemical_list: D020033:Protein Isoforms; D047392:beta-Cyclodextrins; C108732:methyl-beta-cyclodextrin; D002784:Cholesterol; D000254:Sodium-Potassium-Exchanging ATPase; D000109:Acetylcholine