Cerebral protective effects of oral Buflomedil administration for 7 days were studied in spontaneously hypertensive rats (SHR). After permanent bilateral carotid artery occlusion (BCAO), the survival rates at 24 hr were 38% and 44% in groups treated with Buflomedil at the doses of 30 mg/kg (n = 16) and 90 mg/kg (n = 15), respectively, which were significantly higher than that in the control group (orally given saline for 7 days), 6%. In rats that survived and given Buflomedil, carbon filling of the brain after BCAO was extended to the territories of the internal carotid artery, while it was restricted to the brainstem and cerebellum in rats died within 3 hr and given either saline or Buflomedil. Local cerebral blood flow (LCBF), monitored by [14C]-Iodoantipyrine autoradiography, was determined at 3 hr after the start of BCAO or at 2 hr after reperfusion in rats orally given either saline or Buflomedil 30 mg/kg for 7 days. Local cerebral glucose utilization (LCGU), monitored by [14C]-Deoxyglucose autoradiography, was determined at 2 hr after reperfusion. At 3 hr after the start of BCAO, the LCBF in the Buflomedil group was higher by 71-128% in the cerebral cortex, 61-150% in the amygdala, caudate-putamen, nucleous accumbens and globus pallidus, and 82% in the internal capsule. At 2 hr after reperfusion, LCBF did not differ between groups, but LCGU in the Buflomedil group was significantly higher by 26-49% in the cerebral cortex, cochlear nuclei and vestibular nuclei than that in the control group. From these results, it is concluded that Buflomedil improved survival rate after permanent BCAO and have beneficial effect on local cerebral blood flow distribution after BCAO in SHR.