AIM: An optimal method for purifying glycyrrhizic acid with D-101 macro resin was developed. METHODS: The contents of glycyrrhizic acid were used as the evaluating criteria, by means of vanlillin-sulfuric acid colorimetry. RESULTS: The optimum technical operations were as follows: 10% ethanol(4 times the volume of the resin) was used to elute glycyrrhizic acid; both the current velocity of absoring and eluting were 2 mLmin, pH of the sample was 5.8 , concentration of the sample was 9 mgmL (weight of the raw materialvolume). CONCLUSION: The results show that D-101 macro resin is suitable for absorbing and purifying glycyrrhizic acid.

Aim To investigate the change of miR-124 expression in methamphetamine-induced addiction in PC12 cells and the possible regulatory mechanism that it involves.Methods PC12 cells were randomly divided into 6 groups as follows: control group, methamphetamine group, agomir Negative Control group, miR-124 agomir group, agomir Negative Control+methamphetamine group and miR-124 agomir+methamphetamine group.After the treatment, the total RNA and protein were extracted in PC12 cells.The expression of miR-124 was measured by Real-time PCR and the expression of GluR2 was determined by Western blot in PC12 cells.Results Compared with those in the control group, the expression of miR-124 was remarkably decreased and the expression of GluR2 was significantly increased in the methamphetamine group in PC12 cells.Compared with those in the agomir Negative Control+methamphetamine group, the expression of miR-124 was remarkably increased and the expression of GluR2 was significantly decreased in the miR-124 agomir+methamphetamine group in PC12 cells.Conclusion MiR-124 might involve in methamphetamine-induced addiction in PC12 cells by inhibiting GluR2.