['To investigate the effects of the intratracheal and iv administration of bleomycin on the contraction and endothelially dependent vasodilation of rat pulmonary arteries in vitro.', 'Prospective pharmacologic study.', 'National Heart and Lung Institute, London, UK.', 'Intratracheal saline, intratracheal and iv bleomycin.', 'Rats treated with intratracheal bleomycin developed a significant increase in mean lung wet/dry weight ratio (5.6 +/- 0.4 [SEM] vs. 3.9 +/- 0.1, p less than .05) when compared with saline-treated control animals, confirming the development of pulmonary edema. However, these rats displayed normal relaxant responses to the endothelially dependent vasodilator acetylcholine and a normal contractile response to phenylephrine in vitro. Intravenous bleomycin had no effect on either wet/dry weight ratio or the response to either drug.'] Does bleomycin-induced acute lung injury in the rat influence pulmonary vascular responsiveness in vitro?