Objective To observe the effect of acupuncture plus moxibustion on the synaptic ultrastructure and expression of synaptic skeleton related proteins in the prefrontal cortex(PFC)of heroin re-addicted rats

so as to reveal its mechanisms underlying improvement of heroin addiction.Methods Twenty-four Wister rats(half male and half female)were randomly divided into normal control

model and acupuncture groups(n=8 in each group).The heroin re-addicted model was established by muscular injection of heroin into the hind limbs for 8 days(incremental 0.8—3.6 mg

once daily for 6 days

and twice daily for2 days)

followed by conventional breeding for 5 days(detoxification)

the procedure(addition-detoxification)was repeated3 cycles.For rats of the acupuncture group

"Baihui"(GV20)was needled with filiform needles which were retained for 30 min

and moxibustion was then applied to bilateral"Shenshu"(BL23)for 30 min.The treatment was conducted once daily during the detoxification.On the 39 th day of experiment

the bilateral prefrontal cortex tissues were sampled for examining the ultrastructure by using transmission electron microscope(TEM)after fixative solution immersion and for determining the expression of genes and proteins of activity-regulated cytoskeleton-associated protein(Arc)

microtubule-asso-ciated protein-2(MAP-2)and microtubuleassociated protein Tau(Tau)with quantitative real-time PCR and Western blot

respectively.Results After modeling

the expression levels of Arc mRNA and protein were significantly up-regulated

and those of MAP-2 and Tau mRNA and proteins obviously down-regulated in the model group relevant to the normal control group(P<0.05).Following the intervention

the up-regulated Arc protein and mRNA and the down-regulated MAP-2 and Tau were obviously reversed relevant to the model group(P<0.05).Outcomes of TEM showed unclear pre-and post-membranes of the synapses

narrowing of the synaptic gap and non-uniform of the density of the thickened dense plaque after modeling

which was relatively milder in the acupuncture group.Conclusion Acupuncture plus moxibustion can improve changes of synaptic ultrastructure in heroin re-addicted rats

which may be related to their effect in regulating the expression of some synaptic skeleton proteins and genes.