Objective To observe the effect of electroacupuncture(EA) on hippocampal structure in splenic asthenia pedo-rats.Methods A total of 15 SD male rats were randomly assigned to normal control group(n=5)

model group(n=5) and EA group(n=5).Splenic asthenic syndrome model was established by intragastric administration of rhubarb and intraperitoneal injection of Reserpine for 14d.EA(1mA

3Hz/15Hz) was applied to bilateral "Zusanli"(ST 36) and "Sanyinjiao"(SP 6) for 20min

once a day for 14 days.The cellular structure of hippocampus was observed by light microscope and transmission electron microscope.Results Optical microscopic observation showed that in normal control group

the cellular nucleus was distinct

and the granular cell layer well-arranged and tight.In model group

the intracellular space was widened

and the granular cell layer was out of order in the arrangement.In EA group

the cellular nucleus and the granular cell layer were nearly normal.Results of the electronic microscope showed that cells in model group had a karyopyknosis with irregular appearance and clear incisure

and some of them presented dissolving and necrotic phenomena;and those in EA group were milder in injury

had nearly-normal nucleus with visible nucleoli and relatively-intact nuclear membrane.Regarding the cellular plasma

in comparison with rich normal organelles of control group

the mitochondria in model group were swelling

with vague

dissolved and broken cristae

while in EA group

majority of the organelles were well-kept

and slightly dissolved mitochondrial cristae found.In regard to the synaptic structure

in comparison with control group

synaptic apomorphosis and swelling mitochondria were found in model group.While in EA group

milder swelling and hydropic degeneration were seen.Different from the distinct pre-and post-synaptic membrane and synaptic vesicles of control group

the synaptic clefts and vesicles of model group were vague in the profile;while those in EA group were nearly-normal.Conclusion Electroacupuncture can effectively relieve splenasthenic syndrome induced pathohistological changes of neurons of the hippocampus in the rat.