Effect of psoralen on the cloned Kv3.1 currents.
Arch Pharm Res
; 32(3): 407-12, 2009 Mar.
Article
em En
| MEDLINE
| ID: mdl-19387585
ABSTRACT
The psoralen, a furocoumarin derivative, on the cloned neuronal rat Kv3.1 channels stably expressed in Chinese hamster ovary cells was investigated using the whole-cell patch-clamp technique. Psoralen reduced Kv3.1 whole-cell currents in a reversible concentration-dependent manner, with an IC50 value and a Hill coefficient of 2.3 +/- 0.03 microM and 0.9 +/- 0.08, respectively. Psoralen accelerated the decay rate of inactivation of Kv3.1 currents without modifying the kinetics of current activation. The psoralen-induced inhibition of Kv3.1 channels was voltage-dependent, with a steep increase over the voltage range of channel opening. However, the inhibition exhibited voltage independence over the voltage range in which channels are fully activated. Psoralen slowed the deactivation time course, resulting in a tail crossover phenomenon when the tail currents, recorded in the presence and absence of psoralen, were superimposed. Inhibition of Kv3.1 by psoralen was use-dependent at a frequency of 1 Hz. The present results suggest that psoralen acts on Kv3.1 currents as an open-channel blocker.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Potássio
/
Bloqueadores dos Canais de Potássio
/
Canais de Potássio Shaw
/
Ficusina
/
Proteínas do Tecido Nervoso
Limite:
Animals
Idioma:
En
Revista:
Arch Pharm Res
Ano de publicação:
2009
Tipo de documento:
Article