Effect of hydrocortisone on platelet activating factor induced lung edema in isolated rabbit lungs

The effect of hydrocortisone on platelet activating factor (PAF)-induced pu lmonary edema is studied, Thirty four isolated and perfused rabbit lung pre parations were used: eight control preparations, eight PAF preparations wit h two doses of PAF called low dose (LD = 0.5 mu g/kg of rabbit weight) and high dose (HD = 1 mu g/kg of rabbit weight). Eighteen preparations divided in three groups of six were pretreated with doses of 20, 200 and 2000 mg of hydrocortisone and later given the same doses of PAF as described above. H ydrocortisone significantly decreased (P < 0.05) the effect of PAF LD over the pulmonary arterial pressure (Ppa) in the 200 and 2000 mg groups (58 and 89% decrease, respectively) and it significantly decreased (P < 0.05) the effect of PAF HD over Ppa in all hydrocortisone pretreated groups (48, 70 a nd 96% decrease: respectively). Fluid filtration rate (FFR) increases media ted by PAF HD were significantly inhibited (P < 0.05) in the 200 and 2000 m g groups (64 and 96% decrease, respectively). We conclude that hydrocortiso ne inhibits the effect of PAF over the pulmonary circulation. (C) 2000 Publ ished by Elsevier Science B.V. All rights reserved.