Your browser doesn't support javascript.
loading
Coronary denervation attenuates coronary constriction induced by muscarinic receptor stimulation in pigs.
Cinca, J; Mont, L; Carreño, A; Mourelle, M; Rodés, J; Domingo, A; Soler-Soler, J.
Afiliação
  • Cinca J; Departamento de Medicina, Hospital General Universitari Vall d'Hebron, Barcelona, Spain. jcinca@ar.vhebron.es
Cardiovasc Res ; 32(2): 311-9, 1996 Aug.
Article em En | MEDLINE | ID: mdl-8796118
OBJECTIVES: We tested the hypothesis that coronary denervation attenuates the reactivity of the coronary vessel to cholinergic stimulation. METHODS: Heart rate, left ventricular (LV) pressure, LV dP/dt, coronary blood flow at the left anterior descending (LAD) coronary artery, and epicardial ECG mapping were measured before and after topical application of 1% methacholine to the LAD in 10 pigs anesthetized with alpha-chloralose (100 mg/kg, i.v.); these were compared with 10 other pigs submitted 2 weeks previously to a denervation of the LAD with phenol. Coronary denervation was confirmed in all cases by adrenergic histofluorescence and by acetyl-cholinesterase staining. Isolated LAD rings from 10 additional pigs (5 controls and 5 treated with phenol) were stimulated with endothelin-1 to verify whether phenol affected coronary reactivity to noncholinergic stimulation. RESULTS: Methacholine induced a fall in coronary blood flow (10.3 +/- 5.3 ml/min vs 4.8 +/- 6.2 ml/min, ANOVA: P < 0.001), a drop in systolic LV pressure (113 +/- 19 mmHg vs 93 +/- 19 mmHg, P < 0.001) and LV dP/dt (1608 +/- 363 mmHg/s vs 1203 +/- 302 mmHg/s, P = 0.02) and elevation of the ST segment (1.4 +/- 0.9 vs 11.1 +/- 4.7 mV, P < 0.001) in controls. These changes were not preceded by heart rate variations and were inhibited by atropine. As compared to controls, phenol-treated pigs showed a smaller decline in coronary blood flow (13.1 +/- 4.5 ml/min to 10.4 +/- 5.4 ml/min, P < 0.001), a lower drop in LV pressure (107 +/- 20 mmHg to 100 +/- 19.7 mmHg, P < 0.001) and lesser ST segment elevation (2.2 +/- 1.7 mV to 5.6 +/- 4.2 mV, P < 0.001). Isolated LAD rings contracted after exposure to endothelin-1 in both controls and phenol-treated pigs (3.5 +/- 0.7 g vs 2.4 +/- 1.0 g, P = 0.06). CONCLUSIONS: Coronary denervation attenuates coronary constriction induced selectively by direct muscarinic receptor stimulation in the in situ pig heart.
Assuntos
Buscar no Google
Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Simpatectomia Química / Vasoconstrição / Cloreto de Metacolina / Agonistas Muscarínicos / Vasos Coronários Tipo de estudo: Prognostic_studies Limite: Animals Idioma: En Ano de publicação: 1996 Tipo de documento: Article
Buscar no Google
Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Simpatectomia Química / Vasoconstrição / Cloreto de Metacolina / Agonistas Muscarínicos / Vasos Coronários Tipo de estudo: Prognostic_studies Limite: Animals Idioma: En Ano de publicação: 1996 Tipo de documento: Article