Figure 4. Alterations in the plasma amino acid levels in CD38-KO mice. Mice Mice were entrained in 12 hr Light - 12 hr Dark cycles and blood was drawn at indicated times. Amino acid levels in plasma were determined as described in Materials and Methods. Amino acids that displayed statistically significant differences in abundance between the wild type and the CD38-KO mice are shown here. *, p<0.05; **, p<0.01 compared to the corresponding wild type, n= 3 each time point.