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Type 2 ryanodine receptors are highly sensitive to alcohol.

ABSTRACT: Exposure to ethanol levels reached in circulation during alcohol intoxication (>10mM) constricts cerebral arteries in rats and humans. Remarkably, targets and mechanisms underlying this action remain largely unidentified. Artery diameter is regulated by myocyte Ca(2+) sparks, a vasodilatory signal contributed to by type 2 ryanodine receptors (RyR2). Using laser confocal microscopy in rat cerebral arteries and bilayer electrophysiology we unveil that ethanol inhibits both Ca(2+) spark and RyR2 activity with IC50<20 mM, placing RyR2 among the ion channels that are most sensitive to ethanol. Alcohol directly targets RyR2 and its lipid microenvironment, leading to stabilization of RyR2 closed states.

SUBMITTER: Ye Y

PROVIDER: S-EPMC4193545 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature

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Type 2 ryanodine receptors are highly sensitive to alcohol.

Ye Yanping Y Jian Kuihuan K Jaggar Jonathan H JH Bukiya Anna N AN Dopico Alex M AM

FEBS letters 20140312 9

Exposure to ethanol levels reached in circulation during alcohol intoxication (>10mM) constricts cerebral arteries in rats and humans. Remarkably, targets and mechanisms underlying this action remain largely unidentified. Artery diameter is regulated by myocyte Ca(2+) sparks, a vasodilatory signal contributed to by type 2 ryanodine receptors (RyR2). Using laser confocal microscopy in rat cerebral arteries and bilayer electrophysiology we unveil that ethanol inhibits both Ca(2+) spark and RyR2 ac ...[more]

PMID: 24631538

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