Figure 1From: Altered expression of circadian clock gene, mPer1, in mouse brain and kidney under morphine dependence and withdrawal The conditioned place preference (CPP) results. Data of CPP in mice are given as mean (± S.E.M.) under the different conditions. a: CPP in the Con and MD groups (Con group after the 8th day of saline injection, MD group after the 8th day of morphine injection, * p < 0.05 tested by Student's t-test) b: CPP in the MW group (MW group after the 8th day morphine injection and after 5th day of morphine withdrawal).Back to article page