Vasodilating effect of flunarizine in anesthetized dogs

The effect of flunarizine on the peripheral vascular beds of anesthetized dogs was investigated and compared with those of cinnarizine and papaverine. Flunarizine, cinnarizine and papaverine generally caused hypotension, tachycardia and vasodilation, although bradycardia preceded by tachycardia was observed after the high doses of flunarizine and cinnarizine. There was no significant difference between the changes in vertebral, hindquarter and mesenteric vascular resistances induced by flunarizine and cinnarizine, while the duration of the vasodilating effect of flunarizine was longer than that of cinnarizine especially in the vertebral vascular bed. Furthermore, the duration of the effect of flunarizine on the vertebral vascular bed was significantly longer than that on the mesenteric vascular bed.