Respiration Physiology 114 (1998) 153 – 160 Effect of Fenoterol on PAF-induced lung edema in isolated and perfused rabbit lungs Liuska Pesce, Sandra Tristano, Eliot Friedman, Alejandro Comellas, He ´ctor Marcano, Roberto Sanchez de Leo ´n* Unidad de Fisiologia Respiratoria, Instituto de Medicina Experimental, Facultad de Medicina, Escuela Luis Razetti, Uniersidad Central de Venezuela, Caracas, Venezuela Accepted 24 August 1998 Abstract We have studied the effects of fenoterol on PAF-induced response in pulmonary circulation. We used 28 isolated and perfused rabbit lungs preparations: eight control preparations (CP), four vehicles preparations (VP), eight PAF preparations (PP) with two doses of PAF, one called low dose (LD =0.5 g/kg of weight) and the other high dose (HD =1 g/kg of weight) and eight Fenoterol preparations (FP) which we administered 0.05 mg of Fenoterol for 15 min, followed by a LD and HD of PAF. FP prevented elevation of pulmonary artery pressure (Ppa) as compared to PP, at LD of PAF: 12.615 (CI 95%: 8.57–20.885) versus 83.705 (CI 95%: 50.55–114.3) cm of water; and at HD of PAF: 19.38 (CI 95%: 11.235–28.94) versus 205.1 (CI 95%: 141.3–271) cm of water respectively. FP prevented the increase in fluid filtration rate (FFR) observed in PP at both doses of PAF LD: 0.765 (CI 95%: 0.07–3.385) versus -0.01 (CI 95%: -0.05–0.005) g/min; HD: 5.515 (CI 95%: 2.425–8.865) versus 0.03 (CI 95%: 0–0.33) g/min. Our results suggest that PAF has a vasoconstrictor effect that produces lung edema and this effect is inhibited by fenoterol. © 1998 Published by Elsevier Science B.V. All rights reserved. Keywords: Disease; Acute Respiratory Distress Syndrome; Lung edema; Hypertension; Pulmonary; Mammals; Rabbit; Mediators; Platelet activating factor; Pharmacological agents; Pulmonary blood flow; Fenoterol 1. Introduction Platelet Activating Factor (PAF) has been defined as a group of choline-containing phospho- lipids that stimulate platelets (Mc Manus et al., 1993). PAF is synthesized by the majority of inflammatory cells and by the endothelium, being * Corresponding author. Present address: POBA Interna- tional 281, PO Box 025255, Miami, FL 33102, USA. Tel.: +1-582-5086302; fax: +1-582-7316856; e-mail: rsanchez@ven.net www.rsdl.com. 0034-5687/98/$ - see front matter © 1998 Published by Elsevier Science B.V. All rights reserved. PII:S0034-5687(98)00082-6