Objective To compare the effects of electroacupuncture(EA) stimulation of "Gastric Problem Formula" ["Neiguan"(PC 6)

"Zhongwan"(CV 12) and "Zusanli"(ST 36)] on electrical activities of neurons of medullary subnucleus reticularis dorsalis(SRD) of the rat.Methods Experiments were performed on SD rats anesthetized by 10% urethane(1.0-1.5 g/kg).Under artificial ventilation and immobilization(2% gallamine triethiodide

5 ml/kg)

extracelluar discharges were recorded by glass micropipettes inserted into SRD of the medulla(Caudal to the Obex:-1.0——2.0 mm

L/R: 0.5-l.5 mm

H: 0.6-1.5 mm below the medullary surface).Following getting stable recordings

the acupuncture needle inserted in "Neiguan"(PC 6) was manipulated moderately(twisting range: 120°

frequency: 80 times/min) for 30 s.The same manipulation was performed at "Zhongwan"(CV 12) and "Zusanli"(ST 36) separately.Results After moderate acupuncture stimulation

in the recorded 13 SRD neurons

the discharges were increased from(1.67±0.35) spikes/s to(17.55±1.40) spikes/s for "Neiguan"(PC 6)

from(2.35±0.43) spikes/s to(16.96±1.83) spikes/s for "Zhongwan"(CV 12)

and from(1.83±0.37) spikes/s to(17.39±1.58) spikes/s for "Zusanli"(ST 36).No apparent differences were found among 3 acupoints in their responses to manual manipulation.Conclusion Moderate acupuncture stimulation of "Neiguan"(PC 6)

"Zhongwan"(CV 12) and "Zusanli"(ST 36) can effectively activate spontaneous discharges of SRD neurons in the rat.