Effects of Panax Notoginseng on phosphorylated CREB protein expression and CREB/DNA binding activity in hippocampus of morphine withdrawal rats

    YAN Yuª²Xian, HU Wenª²Liang, CONG Bin, NIU Zengª²Qiang, LI Shuª²Jin, YU Lei, MA Chunª²Ling, ZHANG Guoª²Zhong, ZUO Min

    Department of Forensic Medicine, Hebei Medical University, Shijiazhuang 050017, China, Department of Training£¬Medical College of People¬ðs Armed Police Forces, Tianjin 300162, China

    ¡¾Abstract¡¿ AIM: To investigate the effects of Panax Notoginseng (PNS) on the expressions of CREB, phosphorylated CREB (pCREB) and CREB/DNA binding activity in hippocampus of the morphine dependent rats and the naloxoneª²precipitated withdrawal syndrome rats, and to explore the mechanism by which PNS inhibits the morphine withdrawal symptom in rats. METHODS: The models of morphine physical dependent rats and withdrawal syndrome were established by subcutaneous injection of morphine in gradually increasing doses and abdominal cavity injection of naloxone respectively. The rats were treated with PNS by intragastric administration at various doses simulª²taneously when administrated with morphine. The effects of morphine on the expressions of CREB, pCREB, CREB/DNA binding activity in hippocampus were detected by Western blot and electrophoresis mobility shift assay (EMSA). RESULTS: ¢ÙThe CREB protein expression in hippocampus was not significantly statistically different in morphine physical dependent group (MOR), naloxone precipitated withdrawal group (NAL) and PNS groups compared with control group (P>0.05); ¢ÚThe pCREB protein expression and CREB/DNA binding activity in hippocampus were not significantly increased in MOR compared with control group and were significantly increased in NAL compared with MOR and control groups; ¢ÛPNS could doseª²depenª²dently downregulate the increased expression of pCREB and CREB/DNA binding activity in hippocampus induced by naloxoneª²precipitated withdrawal. CONCLUSION: PNS could inhibit the expression of pCREB and CREB/DNA binding activity in hippocampus in a doseª²dependent manner. ......