title: Phosphoramidon potentiates the endothelin-1-induced bronchopulmonary response in guinea-pigs.
abstract: We investigated the effect of the endopeptidase-inhibitor, phosphoramidon, on the bronchopulmonary response induced by endothelin-1 in vivo or in isolated perfused lungs. In vivo aerosol administration of 1 or 3 ?g/ml endothelin-1 for 2 min provoked no significant bronchopulmonary response. When awake animals were pretreated by an aerosol of phosphoramidon (0.1 mM, for 15 min), the bronchopulmonary response induced by 1 and 3 ?g/ml endothelin-1 was markedly enhanced. In isolated guinea-pig lungs, aerosol administration of endothelin-1 (3 ?g/ml, for 2 min) evoked a low increase in pulmonary inflation pressure. Treatment of awake animals with an aerosol of phosphoramidon before lung recollection led to a significant potentiation of the endothelin-1-induced increase in pulmonary inflation pressure. These results demonstrate that phosphoramidon potentiates the in vivo and in vitro bronchopulmonary response evoked by low doses of endothelin-1 and suggest that endopeptidase-like enzymes present in the airway tissue modulate the effect of the peptide.
authors.affiliation: Institut Henri Beaufour, 1, avenue des Tropiques, 91952 Les Ulis Cedex, France.
authors.forename: E
authors.initials: E
authors.lastname: Boichot
authors.forename: F
authors.initials: F
authors.lastname: Pons
authors.forename: V
authors.initials: V
authors.lastname: Lagente
authors.forename: C
authors.initials: C
authors.lastname: Touvay
authors.forename: J M
authors.initials: JM
authors.lastname: Mencia-Huerta
authors.forename: P
authors.initials: P
authors.lastname: Braquet