Two types of voltage-dependent outward potassium currents in smooth muscle cells of rabbit basilar artery
The Korean Journal of Physiology and Pharmacology
;
: 169-183, 1997.
Artigo
em Inglês
| WPRIM
| ID: wpr-728635
ABSTRACT
We have investigated the two types of voltage-dependent outward potassium (K) currents, i.e. delayed rectifier K current (I-K(V)) and 'A-like' transient outward K current (I-to) with patch-clamp technique in single smooth muscle cells (SMCs) isolated from rabbit basilar artery, and investigated the characteristics of them. The time-courses of activation were well fitted by exponential function raised to second power (n-2) in I-K(v) and fourth power (n-4) in I-to. The activation, inactivation and recovery time courses of I-to were much faster than that of I-K(V). The steady-state activation and inactivation of I-K(V) was at the more hyperpolarized range than that of I-to contrary to the reports in other vascular SMCs. Tetraethylammonium chloride (TEA; 10 mM) markedly inhibited I-K(V) but little affected 1-to. 4-Aminopyridine (4-AP) had similar inhibitory potency on both currents. While a low concentration of Cd-2+ (0.5 mM) shifted the current-voltage relationship of I-to to the positive direction without change of maximum conductance, Cd-2+ did not cause any appreciable change for I-K(V).
Texto completo:
DisponíveL
Índice:
WPRIM (Pacífico Ocidental)
Assunto principal:
Potássio
/
Artéria Basilar
/
4-Aminopiridina
/
Técnicas de Patch-Clamp
/
Tetraetilamônio
/
Miócitos de Músculo Liso
/
Músculo Liso
Idioma:
Inglês
Revista:
The Korean Journal of Physiology and Pharmacology
Ano de publicação:
1997
Tipo de documento:
Artigo
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