Epileptiform discharge induced by microinjection of penicillin in the rat's amygdala was attenuated after acupuncture of certain "acupoints", as revealed by reduction of frequency and amplitude. The effect of acupuncture was reversed by microinjection of naloxone or 3M-P into peritoneal cavity, thus suggesting the participation of endorphin and GABA in antiepileptic action of acupuncture.