Ionic Mechanisms of Desflurane on Prolongation of Action Potential Duration in Rat Ventricular Myocytes
Yonsei Medical Journal
;
: 204-212, 2012.
Artículo
en Inglés
| WPRIM
| ID: wpr-145830
ABSTRACT
PURPOSE:
Despite the fact that desflurane prolongs the QTC interval in humans, little is known about the mechanisms that underlie these actions. We investigated the effects of desflurane on action potential (AP) duration and underlying electrophysiological mechanisms in rat ventricular myocytes. MATERIALS ANDMETHODS:
Rat ventricular myocytes were enzymatically isolated and studied at room temperature. AP was measured using a current clamp technique. The effects of 6% (0.78 mM) and 12% (1.23 mM) desflurane on transient outward K+ current (I(to)), sustained outward current (I(sus)), inward rectifier K+ current (I(KI)), and L-type Ca2+ current were determined using a whole cell voltage clamp.RESULTS:
Desflurane prolonged AP duration, while the amplitude and resting membrane potential remained unchanged. Desflurane at 0.78 mM and 1.23 mM significantly reduced the peak I(to) by 20+/-8% and 32+/-7%, respectively, at +60 mV. Desflurane (1.23 mM) shifted the steady-state inactivation curve in a hyperpolarizing direction and accelerated inactivation of the current. While desflurane (1.23 mM) had no effects on I(sus) and I(KI), it reduced the L-type Ca2+ current by 40+/-6% (p<0.05).CONCLUSION:
Clinically relevant concentrations of desflurane appear to prolong AP duration by suppressing Ito in rat ventricular myocytes.
Texto completo:
Disponible
Índice:
WPRIM (Pacífico Occidental)
Asunto principal:
Potenciales de Acción
/
Canales de Potasio
/
Ratas Sprague-Dawley
/
Técnicas de Placa-Clamp
/
Anestésicos por Inhalación
/
Canales de Calcio Tipo L
/
Miocitos Cardíacos
/
Sistema de Conducción Cardíaco
/
Ventrículos Cardíacos
/
Isoflurano
Límite:
Animales
Idioma:
Inglés
Revista:
Yonsei Medical Journal
Año:
2012
Tipo del documento:
Artículo
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