Block of outward current in cardiac Purkinje fibers by injection of quaternary ammonium ions.
J Gen Physiol
; 79(6): 1041-63, 1982 Jun.
Article
em En
| MEDLINE
| ID: mdl-6286842
ABSTRACT
We have studied the effects of iontophoretic injection of the quaternary ammonium compounds tetraethylammonium (TEA) and tetrabutylammonium (TBA) in cardiac purkinje fibers. We find that TBA(+) is a more effective blocker than TEA(+), but injection of either compound reduces the time-dependent outward plateau currents, transient outward current (I(to)), and the delayed rectifier (I(x)). Our findings provide evidence that these outward cardiac currents are carried by channels that in some respects are pharmacologically similar to squid axon potassium channels. We demonstrate that this procedure is a new tool that can be useful in the analysis of membrane currents in the heart.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Ramos Subendocárdicos
/
Compostos de Tetraetilamônio
/
Sistema de Condução Cardíaco
/
Compostos de Amônio Quaternário
/
Canais Iônicos
Limite:
Animals
Idioma:
En
Revista:
J Gen Physiol
Ano de publicação:
1982
Tipo de documento:
Article