Effect of platelet-activating factor on bovine pulmonary function

The objectives of this study were to determine whether the infusion of platelet-activating factor would modify bovine pulmonary function, heart rate and platelet count and whether any such modifications could be antagonised by the prior intravenous injection of a specific antagonist (WEB 2086). In saline-pretreated calves, the respiratory rate, total lung resistance (RL) and maximal changes in transpulmonary pressure (delta Ptp) were significantly increased whereas lung dynamic compliance (CLdyn), tidal volume (VT), platelet count and heart rate were significantly decreased. The changes in RL, CLdyn, VT and delta Ptp were abolished by pretreatment with WEB 2086, whereas respiratory rate remained significantly increased to 125 per cent of the baseline value, but less than in the saline-pretreated calves in which it was 250 per cent of the baseline value.