Objective To observe the effect of electroacupuncture(EA)stimulation of "Shenmen"(HT 7)and"Taiyuan"(LU 9)on P 50event-related potentials in rabbits with acute myocardial ischemia(AMI)

so as to evaluate the specificity of function of different acupoints.Methods Chinchilla rabbits were randomized into normal control

model

Shenmen(HT 7)and Taiyuan(LU 9)groups(n=10/group).AMI model was established by temporary occlusion of the descending anterior branch of the left coronary artery.EA(1mA

2Hz)was applied to bilateral HT 7and LU 9for 15 min.The anesthetized-rabbit's heart rate(HR)was recorded by using a BIOPAC system and the latency and amplitude of auditory sensory gating potential P 50 were measured by paired clicks auditory conditioning(S 1-P 50)/testing(S 2-P 50)stimulus paradigm using a Neuroscan workstation.Results In comparison with the normal control group

the HR was significantly decreased in the model group and significantly increased in the HT 7group than in the model group(P<0.01).Compared to the normal control group

the amplitude of S 2-P 50 and ratio of amplitude of S 2-P 50/S 1-P 50 were significantly increased in the model group(P<0.01)

and remarkably down-regulated in the HT 7group than in the model group(P<0.01)

suggesting an inhibitory effect of EA stimulation of HT 7on cerebral cortical auditory gating potential in AMI rabbits.No significant changes were found in the latencies of S 1-P 50

S 2-P 50 potentials in both HT 7and LU 9groups and in the HR

amplitude of S 2-P 50 and ratio of amplitude of S 2-P 50/S 1-P 50 in the LU 9group(P>0.05).Conclusion EA stimulation of HT 7can correct AMI induced decrease of HR and increase of P 50 potential amplitude in AMI rabbits

while EA of LU 9has no this effect

suggesting a relatively specific effect of different acupoints on cortical sensory gating.