Effects of gamma-oryzanol were studied on gastric lesions induced by both conditioned emotional stimuli (CES) and REM sleep deprivations and on the facilitation of small intestinal propulsive activity by CES in mice. The CES were given by the communication box method, and the REM sleep deprivations were performed by a modified flower pot method. The incidence of gastric lesions in responder mice induced by CES was reduced by twice p.o. administrations at 6 hr interval of gamma-oryzanol at 200 and 500 mg/kg, oxazolam at 2 mg/kg and atropine at 1-10 mg/kg. The incidence in sender mice was also reduced by gamma-oryzanol at 200 and 500 mg/kg. In addition, the incidence of gastric lesions induced by REM sleep deprivation was also reduced by single administration of gamma-oryzanol at 100 and 200 mg/kg and oxazolam at 5 mg/kg. The facilitation of small intestinal propulsive activity in responder mice induced by CES was suppressed by gamma-oryzanol at 100 and 200 mg/kg and atropine at 10 mg/kg. These results indicate that gamma-oryzanol has an antiulcerative action on gastric lesions induced by CES and REM sleep deprivation, and it has a suppressive action on the facilitation of intestinal propulsion induced by CES.