COMPARED EFFECTS OF NATRIURETIC PEPTIDES ON OVALBUMIN-INDUCED ASTHMATIC MODEL

We compared the effects of natriuretic peptides on antigen-induced bro nchoconstriction and airway microvascular leakage in sensitized guinea pigs. Anesthetized male guinea pigs, ventilated via a tracheal cannul a, were placed in a plethysmograph to measure pulmonary mechanics for 10 min after challenge with 1 mg/kg of ovalbumin, and then Evans blue dye was extravasated into airway tissue in order to indicate and evalu ate microvascular leakage. Three separate intravenous pretreatments us ing atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and C-type natriuretic peptide (CNP) significantly inhibited the oval bumin-induced bronchoconstriction and microvascular leakage in a dose- dependent manner. These inhibitory effects were mimicked by 8-bromogua nosine 3',5'-cyclic monophosphate. We showed that the rank order of in hibitory potencies, which were mediated by cyclic guanosine 3',5'-mono phosphate, was BNP greater than or equal to ANP > CNP. These results g ave us some clues for the clinical application of the natriuretic pept ides. (C) 1998 Elsevier Science B.V.