[Effects of dilazep on cerebral blood flow under normal conditions and recirculation impairment after cerebral ischemia (author's transl)].

Regional cerebral blood flow (r-CBF) in anesthetized dogs was measured by the H2 clearance method. Cerebral ischemia was induced by permanent ligation of bilateral vertebral arteries (VA) and a 10 min occlusion of bilateral common carotid arteries (CCA). Under normal conditions, dilazep (100 and 300 micrograms/kg i.v.) increased r-CBF dose-dependently without affecting arterial PO2, PCO2 and pH. r-CBF was reduced by 40% during cerebral ischemia. Relative r-CBF rates, as compared with pre-ischemic rates, were 85%, 80%, 77% and 75% at 30, 60, 90 and 120 min after cerebral ischemia, respectively, indicating development of recirculation impairment. Dilazep (100 and 300 micrograms/kg i.v. 30 min before CCA occlusion) did not affect r-CBF reduction during the state of cerebral ischemia, whereas it prevented re-circulation impairment after cerebral ischemia. Papaverine (300 micrograms/kg i.v. 30 min before CCA occlusion) exerted similar effects. These results suggest that dilazep is a potentially effective drug for treating cerebrovascular disorders.