Abstract: AIM: To investigate the protective effects and the mechanisms of prostaglandin E₁(PGE₁) on isch-emia/reperfusion (I/R)-induced lung injury after lung transplantation in rats. METHODS: 36 SD rats were randomly divided into 3 groups (n=12 in each): sham operation group (control group), lung transplantation (LT)group and PGE₁, treatment group. PGEi was admin-istered to the rats through intra-venous way from 10 min before the operation to the end of the reperfusion. The wet/dry ratio of lung, lung permeability index and neutro-phil percentage were detected in bronchoalveolar lavage fluid (BALF). Superoxide dismutase (SOD) and malond-ialdehyde (MDA) of lung tissue were measured by color-imetry.Serum level of tumor necrosis factor a(TNFα) was detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: The wet/dry ratio of lung, lung permeability index and neutrophils percentage in BALF and MDA content of lung tissue in LT group were higher than those in control group(P < 0.01). SOD activity of lung tissue in LT group was lower than that in control group(P < 0.01). Administration of PGE₁, improved the indexes above (P < 0.01). Serum level of TNFα in-creased after lung transplantation compared with the con-trol group. However, PGE₁ treatment reduced the serum levelof TNFα(P<0.01). CONCLUSION: PGE₁ can protect the lung function against I/R injury after lung transplantation. The mechanism is related to its anti-oxi-dative effect and the inhibition of TNFα release and neu-trophils activation.

Key words: lung transplantation, ischemia-reperfu-sion, prostaglandin E₁, tumor necrosis factor a