The influence of cigarette smoke on metabolism of eicosanoids in rat lung in terms of variation of 15-hydroxyeicosatetraenoic acid and 11-dehydrothromboxane B2

Abstract

We investigated the effects of cigarette smoking on metabolism of two eicosanoids, 15-hydroxyeicosatetraenoic acid (15-HETE) and 11-dehydrothromboxane B2 (11-dehydro-TXB2) in the lung. Twelve female Wistar rats aged between 5 and 6 weeks were chosen and the smoking group (SG, n = 6) was compared to the control group (CG, n = 6). Cigarette smoke exposure was performed using a Hamburg-II inhalation apparatus and the dose was 10 cigarettes in 30 min. Bronchoalveolar lavage (BAL) was conducted 30 min after smoking exposure and the recovered BAL fluid was centrifuged at 3000 rpm for 10 min. The levels of 15-HETE and 11-dehydro-TXB2 of the supernatant were measured by radioimmunoassay in each sample. Recovered 15-HETE significantly increased in SG (SG: 490 +/- 109 pg, CG: 191 +/- 63 pg, p less than 0.05), while there was no significant difference in recovered protein (SG: 2.64 +/- 0.50 mg, CG: 2.23 +/- 0.10 mg), 11-dehydro-TXB2 (SG: 128 +/- 13 pg, CG: 156 +/- 7 pg). We conclude that acute cigarette smoke exposure increases recovered BAL fluid 15-HETE, a potent inflammatory mediator and that 15-HETE in BAL fluid may indicate lung injury induced by smoking.