Objective To observe the anti-seizure effect of electroacupuncture(EA) at differentsites regions of the auricle in awake rats.Methods Sixty male SD rats were randomly divided into model

ear-apex

ear-outer-margin

earlobe

cymba-concha

cavitas-conchae groups(n=10 in each group).A metal microelectrode(diameter: 50μm) was implanted into the somatosensary cortex for recording the field potentials(FPs).Epileptic seizure model was established by intraperitoneal injection of pentylenetetrazol(PTZ

60mg/kg).EA(20Hz

1mA) was applied to ear-apex

ear-outer-margin

earlobe

cymaba-concha and cavitas-conchae for 30min

respectively.The epileptic behavior changes(scores) were determined in the light of Racine's method

and the epileptic seizure was assessed according to the epileptic FPs(5-folds above the basic amplitude) of the cerebral cortex.Results In comparison with the model group

the latency of the first seizure of epilepsy in the ear-outer-margin

earlobe

cymba-concha

cavitas-conchae groups were increased significantly(P<0.01)

while the scores of epileptic behavior and the duration of seizure shown by FPs decreased considerably in the ear-apex

ear-outer-margin

earlobe

cymba-concha

cavitas-conchae groups(P<0.01).Comparison among the five EA treatment groups showed that the effects of both cymba-concha and cavitas-conchae groups were significantly superior to those of ear-apex

earlobe and ear-outer-margin groups in increasing the latency of the first seizure of epilepsy

and reducing the scores of the epileptic behavior and seizure duration(P<0.01).No significant differences were found between the cymba-concha and cavitas-conchae groups in the above-mentioned 3 indexes(P>0.05).Conclusion EA of cymba-concha and cavitas-conchae has a good effect in suppressing epileptic seizures

which may be mediated via the auricular branch of the vagus nerve.