Dominant role of N-type Ca2+ channels in evoked release of norepinephrine from sympathetic neurons.
Science
; 239(4835): 57-61, 1988 Jan 01.
Article
em En
| MEDLINE
| ID: mdl-2447647
ABSTRACT
Multiple types of calcium channels have been found in neurons, but uncertainty remains about which ones are involved in stimulus-secretion coupling. Two types of calcium channels in rat sympathetic neurons were described, and their relative importance in controlling norepinephrine release was analyzed. N-type and L-type calcium channels differed in voltage dependence, unitary barium conductance, and pharmacology. Nitrendipine inhibited activity of L-type channels but not N-type channels. Potassium-evoked norepinephrine release was markedly reduced by cadmium and the conesnail peptide toxin omega-Conus geographus toxin VIA, agents that block both N- and L-type channels, but was little affected by nitrendipine at concentrations that strongly reduce calcium influx, as measured by fura-2. Thus N-type calcium channels play a dominant role in the depolarization-evoked release of norepinephrine.
Buscar no Google
Base de dados:
MEDLINE
Assunto principal:
Norepinefrina
/
Cálcio
/
Gânglios Simpáticos
/
Canais Iônicos
Limite:
Animals
Idioma:
En
Ano de publicação:
1988
Tipo de documento:
Article