Effects of sympathetic activity and galanin on cardiac vagal action in anaesthetized cats.
J Physiol
; 448: 225-35, 1992 Mar.
Article
em En
| MEDLINE
| ID: mdl-1375635
ABSTRACT
1. Stimulation of the right cardiac sympathetic nerve for 3 or 5 min at 16 Hz in the presence of effective beta-adrenoceptor blockade evoked prolonged attenuation of subsequent cardiac vagal action in anaesthetized cats. Concurrent sympathetic and vagal stimulation, both at 16 Hz for the same period of time as sympathetic stimulation alone, reduced or abolished the inhibition of vagal action which followed when sympathetic stimulation was given alone. 2. A series of three successive intravenous injections of galanin all caused attenuation of vagally induced slowing of the heart, but the effect of each injection was less than that of the previous one. A fourth injection of galanin given after a 45 or 60 min rest period showed return of sensitivity. 3. Sympathetic stimulation at 16 Hz for 5 min was less efficient in causing attenuation of vagal slowing when applied following the administration of exogenous galanin. This is consistent with galanin being the mediator of vagal attenuation following sympathetic stimulation.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Peptídeos
/
Sistema Nervoso Simpático
/
Nervo Vago
/
Neuropeptídeos
/
Coração
Idioma:
En
Ano de publicação:
1992
Tipo de documento:
Article