Changes in regional vascular resistance in response to microinjection of L-glutamate into different antero-posterior coordinates of the RVLM in awake rats.
Auton Neurosci
; 87(2-3): 301-9, 2001 Mar 23.
Article
em En
| MEDLINE
| ID: mdl-11476293
Changes in mean arterial pressure (MAP) and in regional vascular resistance (RVR, hindquarter, mesenteric and renal) induced by microinjection of L-glutamate into three different antero-posterior coordinates of the rostral ventrolateral medulla (RVLM) [1,200-1,600 (microm (n=10), 1,601-2,000 microm (n=12) and 2,001-2,500 microm (n=6) rostral to the obex] were investigated in unanesthetized rats. Guide cannulas directed towards the RVLM were implanted 4 days prior to the experiments. Doppler probes were implanted around the superior mesenteric, inferior abdominal aorta and left renal arteries and a catheter was inserted into the femoral artery and vein 1 day prior to the experiments. Insertion of the injector into the RVLM produced an increase in baseline MAP, which was back to control levels 2 min later, when L-glutamate was microinjected. Microinjection of L-glutamate (1 nmol/30 nl) into the three antero-posterior coordinates of the RVLM produced an increase in MAP associated with a similar increase in hindquarter, mesenteric and renal vascular resistance, which were back to control 1 min later. Saline into the RVLM produced negligible effects on MAP and RVR. These findings suggest that the sympathetic vasomotor neurons involved in the regulation of the regional vascular resistance in rats are not topographically distributed in the antero-posterior coordinates of the RVLM. However, the experimental methods used to evaluate the topographic distribution of sympatho-vasomotor neurons in the RVLM and the measurement of the regional blood flow may not be precise enough to detect any possible differences.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sistema Nervoso Simpático
/
Resistência Vascular
/
Bulbo
/
Ácido Glutâmico
Limite:
Animals
Idioma:
En
Revista:
Auton Neurosci
Assunto da revista:
NEUROLOGIA
Ano de publicação:
2001
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Holanda