Objective To investigate the effect of morphine on catabolism and anabolism of purine nucleotide in c6 glioma cells. Methods C6 glioma cells were cultured and divided into 3 groups: 1) morphine group: morphine (10 μg/ml culture) was added for 6 h, 12 h, 24 h, 48 h, and 72 h; 2) morphine + naloxone group: naloxone (1 μmol/L) was added for 1 hour and then morphine (10 μg/ml) was added for 24 hours; and 3) control group: normal saline was used for 6, 12, 24, 48, and 72 hours. The C6 glioma cells were centr...