To observe the effect of electro-acupuncture on the relapse to heroin-seeking induced by heroin-related cues after withdrawal from heroin self-administration in rats.Methods:Sixty male Wistar rats were randomized into physiological saline group,withdrawal group A,withdrawal group B,electro-acupuncture(EA)treatment group A and EA treatment group B,with 12 rats in each group.The rats were trained by nose-poke response to self administer heroin (50 μg/kg/per infusion) or saline with one daily 4-h session for 14 consecutive days,the session ended after 25 infusions were eamed or 4 hours had passed,the reinforcement schedule was a progressive ratio.Then rats in withdrawal group A and withdrawal group B were withdrawn from heroin for 1 week and 2 weeks respectively,and then they were reintroduced to their training chambers for 4-h relapse testing which was induced by heroin-related environmental cues;And rats in EA treatment group A and EA treatment group B were also withdrawn from heroin for 1 week and 2 weeks respectively,during which they were given EA treatment for 20 min daily,then they received relapse testing;In the meantime,rats in saline group were trained with saline instead of heroin for 14 days as control.after 7 days of withdrawal from saline,they received relapse testing.Results:Following 7-8 days of drug training,the rats began to establish the stable intravenous heroin self-administration behavior;For the stable heroin self-administrating rats that received EA treatment,when they were reintroduced to their training chambers,their heroin-seeking behaviors were obviously inhibited,and this inhibitory effect related to the cumulativeness of EA stimulation.Conclusion:The results suggested that EA could prevent relapse to heroin-seeking to a certain extent.