Electroacupuncture (EA) has been reported to reduce body weight in over weighted subjects both in animal experiments and clinical studies.In the present smdy this effect of EA was tested in lean animals caused by long-term food restriction (FR,food was offered only 1 h per day).Two Hz EA produced a further reduction of body weight in FR rats.Exploration of the mechanisms of action revealed a significant down-regulation of the expression of the orexigenic peptide ghrelin in the stomach and NPY in the hypothalamus,which is in line with the reduction of food intake after EA stimulation.The uncoupling peptide UCP3 which is involved in accelerating energy expenditure was not significantly altered.These results suggest that EA-induced decrease in body weight is due mainly to a reduction of food intake associated with a decrease of the expression of orexigenic peptides ghrelin and NPY,rather than an increase of energy expenditure.