Background.The role of glycine has not been investigated in lung ischemia-reperfusion injury after cold preservation. Furthermore, the role of apoptosis after reperfusion following cold preservation has not been fully understood.Methods.Lewis rats were divided into three groups (n=6 each). In the GLY(−) and GLY(+) groups, isolated lungs were preserved for 15 hr at 4°C after a pulmonary artery (PA) flush using our previously developed preservation solution (ET-K; extracellular-type trehalose containing Kyoto), with or without the addition of glycine (5 mM). In the Fresh group, isolated lungs were reperfused immediately after a PA flush with ET-K. They were reperfused for 60 min with an ex vivo perfusion model. Pulmonary function, oxidative stress, apoptosis, and tumor necrosis factor (TNF)-&agr; expression were assessed after reperfusion.Results.Shunt fraction and peak inspiratory pressure after reperfusion in the GLY(−) group were significantly higher than those in the GLY(+) and Fresh groups. Oxidative damage and apoptosis in the alveolar epithelial cells of the GLY(−) group, assessed by immunohistochemical staining and quantification of 8-hydroxy-2′-deoxyguanosine and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling method, were significantly higher than those of the GLY(+) and Fresh groups. There were correlations among shunt fraction, oxidative damage, and apoptosis. There was no expression of TNF-&agr; messenger RNA in all groups evaluated by the reverse transcription-polymerase chain reaction.Conclusions.Glycine attenuates ischemia/reperfusion injury after cold preservation by reducing oxidative damage and suppressing apoptosis independent of TNF-&agr; in this model. The suppression of apoptosis might ameliorate lung function after reperfusion.