Lesions of the amygdala have long been known to produce hyperphagia and obeisty in cats,dogs and monkeys.However,there were considerable arguments regarding the involvement of specific nuclei.Recently,the posterodorsal amygdala(PDA) is suggested as a possible effective site by small lesions.This effect was more notable in female rats.But the mechanism is still not clear.To better understand whether PDA is a critical site in feeding behavior,we tested the change on food intake by acute electrical stimulation of the PDA of female rats.The possible mechanisms were also explored preliminarily,including the correlated hormones and the brain structures-related.In experiment 1,after 10 min of stimulation with 0.2 ms 100 μA 50 HZ square-wave cathodal pulses on the unilateral PDA of female rats with 23h food deprivation,ad libitum food intake within lh was measured immediately.The mean food consumption was (3.32±1.47) g (n =10),and singnificantly less than the control group [(8.93±2.17) g,n =6,P < 0.001].In experiment 2,using female rats which had fasted for 12h,the serum leptin concentration(RIA) and glucose were determined after 10 min of electrical stimulation (same parameters as in exp.1) on the unilateral PDA.