Objective:To observe the effect of different frequencies of electroacupuncture(EA) of "Zusanli"(ST 36) on the expression of somatostatin(SOM) mRNA in rats' amygdaloid nucleus.Methods: Thirty SD rats were randomized into control

2 Hz-EA and 128 HzEA groups with 10 cases in each group.Left "Zusanli"(ST 36) was punctured and stimulated electrically for 30 min by setting the parameters being 2 Hz and 128 Hz in frequency

3 V in strength

and 1 ms in the duration of waves.After EA

the rats were transcardically perfused with 1% paraformaldehyde and 1.25% glutaraldehyde and 0.1 mol/L phosphate buffer solution.The brain tissues were sampled to cut into sections(40 μm).The expression of SOM mRNA of amygdaloid nucleus was detected by using in situ hybridization technique.Results: Compared with control group

the number of SOM mRNA expression positive neurons and the grey-density values of SOM mRNA expression in amygdaloid nucleus on the bilateral sides increased significantly in 2 Hz and 128 Hz EA groups(P<0.05

0.01).There were significant differences between two EA groups in the number of SOM mRNA expression positive neurons and the grey-density values.Conclusion: Both 2 Hz and 128 Hz EA of "Zusanli" can up-regulate the expression of SOM mRNA in the rat's amygdaloid nucleus.The high frequency of EA has a more obvious effect.