High frequency deep brain stimulation of rats bilateral accumbens inhibits relapse behavior in morphine-dependent rats / 中华行为医学与脑科学杂志

ABSTRACT

Objective To investigate the effect of high frequency stimulation of bilateral nucleus accumbens on relapse behaviors in morphine-dependent rats.Methods Twenty adult SD rats were employed in the experiment.Through stereotactic operation,outer electrode cannula was implanted into rats' bilateral nucleus accumbens.After 5 days of rest,the morphine-dependent rat model with conditioned place preference (CCP) was established through intraperitoneal morphine injection (10 mg/kg).After acquisition of CPP,normal saline was replaced with morphine for CPP extinction training.CPP test was used to exam the effect of extinction.The rats,after being randomly divided into experimental group (morphine+DBS) and control group (morphine+sham DBS),were electrically stimulated using modified DBS circuits.Rats in the experimental group were given high frequency electrical stimulation while the control group was sham stimulation.After consecutive stimulation for 7 days,rats in the two groups were given small dose of morphine (3 mg/kg)to trigger relapse.Results (1) The CPP score increased after the establishment of rat models compared with pre-establishment of the rat models((616.2±74.7) s vs (353.9±84.3) s,P＜0.01).(2) The CPP score after extinction training decreased compared with pre-conditioned CPP score ((456.4± 148.8) s vs (353.9±84.3) s),P=0.0847) and had no statistical difference compared with post-conditioned CPP score ((456.4±148.8) s vs (616.2± 74.7) s,P=0.0219).(3) When the relapse was induced by small doses of morphine within 24h after the last stimulation,the CPP score of the experimental group decreased compared with the CPP score of control group ((330.1 ±212.6) s vs (684.2±230.2)s,P=0.0029),and the relapse was restrained.Conclusion High frequency DBS of bilateral nucleus accumbens can attenuate relapse behavior in rats