Acetaldehyde alters Ca2+-release channel gating and muscle contraction in a dose-dependent manner.
Am J Physiol Cell Physiol
; 286(5): C1188-94, 2004 May.
Article
en En
| MEDLINE
| ID: mdl-15075218
ABSTRACT
We studied whether acetaldehyde, which is produced by alcohol consumption, impacts ryanodine receptor (RyR) activity and muscle force. Exposure to approximately 50-200 microM acetaldehyde enhanced channel activity of frog RyR and rabbit RyR1 incorporated into lipid bilayers. An increase in acetaldehyde to 1 mM modified channel activity in a time-dependent manner, with a brief activation and then inhibition. Application of 200 microM acetaldehyde to frog fibers increased twitch tension. The maximum rate of rise of tetanus tension was accelerated to 1.5 and 1.74 times the control rate on exposure of fibers to 50 and 200 microM acetaldehyde, respectively. Fluorescence monitoring with fluo 3 demonstrated that 200-400 microM acetaldehyde induced Ca(2+) release from the sarcoplasmic reticulum (SR) in frog muscles. Acetaldehyde at 1 mM inhibited twitch tension by approximately 12%, with an increased relaxation time after a small, transient twitch potentiation. These results suggest that moderate concentrations of acetaldehyde can elicit Ca(2+) release from the SR by increasing the open probability of the RyR channel, resulting in increased tension. However, the effects of acetaldehyde at clinical doses (1-30 microM) are unlikely to mediate alcohol-induced acute muscle dysfunction.
Buscar en Google
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Activación del Canal Iónico
/
Canal Liberador de Calcio Receptor de Rianodina
/
Acetaldehído
/
Contracción Muscular
Límite:
Animals
Idioma:
En
Revista:
Am J Physiol Cell Physiol
Asunto de la revista:
FISIOLOGIA
Año:
2004
Tipo del documento:
Article
País de afiliación:
Japón