Acute ozone exposure increases plasma prostaglandin F(2α) in ozone-sensivitive human subjects

Twenty O₃-sensitive and 2O O₃-nonsensitive subjects participated in a study to investigate the effects of disparate O₃ sensitivity on plasma prostaglandin F(2α) (PGF(2α)) responses consequent to exposure to ambient O₃ concentrations. Subjects were selected from a pool of 75 normal healthy college-aged males who had been previously exposed to 0.35 ppm O₃ for 1 h at an exercising V̇E of 60 L/min. The selection criterion used was the observed decrement in FEV₁ after the O₃ exposure: O₃-sensitive, FEV₁ decrement >24%; O₃-nonsensitive, FEV₁ decrement <11%. Each subject was exposed to filtered air and to 0.20 and 0.35 ppm O₃ for 80 min while exercising at a V̇E of 50 L/min. These experimental protocols were divided into two 40-min sessions separated by a period of 4 to 10 min. PGF(2α), FVC, FEV₁, and FEF_25-75 were evaluated before, during, and after each protocol. S(Gaw) and V(tg) were measured before and after each protocol. Plasma PGF(2α) was significantly increased in the O₃-sensitive group during and after the 0.35-ppm O₃ exposure.