Objective To investigate the effect of electroacupuncture (EA) on the activity of extracellular signal-regulated kinase 1/2 (ERK1/2) in the spinal dorsal horn during morphine tolerance in rats.Methods Twenty-five healthy male Sprague-Dawley rats in which intrathecal (IT) catheters were successfully implanted with-out complications were randomly divided into 5 groups (n =5 each):group normal saline (NS) 10 μl IT twice a day × 7 days; group M morphine 10μg (10 μl) IT twice a day × 7 days; group MO morphine 10 μg + missense oligonucleotide (ODN) 10μg (10 μl) twice a day × 7 days; group AO morphine 10 μg + antisense ODN 10 μg (10μl) twice a day×7 days; group EA morphine 10 μg (10μl) twice a day×7 days + EA (frequency 2 Hz,wave length 1 ms,intensity 3 mA).EA of Yanglingquan and Zusanli lasting for 30 min was performed after first IT administration of morphine once a day for 7 days.Mechanical pain threshold (MPT) was measured before IT administration and at day 2,4,6 of IT administration and 1 day after the end of IT administration.The animals were sacrificed after the last MPT measurement,and L3-5 segments of the spinal cord were isolated to detect the expression of ERK1/2 and phosphor-ERK1/2 (p-ERK1/2) in the spinal dorsal horn by Western blot analysis.Results Morphine tolerance developed in groups M,MO and AO,and was lightest in group EA.Compared with group NS,the expression of p-ERK1/2 was significantly up-regulated in groups M and MO,the expression of ERK1/2 was down-regulated in group AO (P ＜ 0.05),and no significant change was found in the indexes mentioned above in group EA (P ＞ 0.05).Compared with groups M and MO,the expression of p-ERK1/2 and ERK1/2 was significantly down-regulated in group AO,and the expression of p-ERK1/2 was down-regulated in group EA (P ＜0.05).Compared with group AO,the expression of p-ERK1/2 and ERK1/2 was significantly up-regulated in group EA (P ＜ 0.05).Conclusion EA can inhibit chronic morphine tolerance-induced increased activity of ERK1/2 in the spinal dorsal horn and alleviate the development of morphine tolerance in rats.

Objective:Normal murine DCs were pulsed with complex of tumor antigen from elemene-combo tumor cell vaccine-heat shock protein 70 of BCG (H TA-HSP70 BCG).Their proliferation and antigen presenting function were evaluated.Methods:The dendritic cells(DCs)were cultured in complete media containing GM-CSF and IL-4 and pulsed with H TA-HSP70 BCG,H TA or HSP70 BCG.Their proliferation and stimulating effects on spleen nonadherent cells were evaluated with MTT assay.Their capability of endocytosing FITC labeled dextran was assayed with FACscan,morphological changes of DC were observed in electron microscope.Results:Proliferation index of DCs pulsed with H TA-HSP70 BCG was 2.107?0.013,proliferation index of DCs pulsed with H TA-HSP70 BCG mixed with normal nonadherent spleen cell was 1.927?0.073.The percent of DCs endocytosed FITC labeled dextran was 58.61%.Above changes were more significant than those of DCs pulsed with H TA or HPS79 BCG.Conclusion:H TA-HPS70 BCG had more potent activity to pulse DC and strengthen antigen presenting of DC.