[Effects of scoparone on hemodynamics in anesthetized rabbits]

The effects of scoparone (Sco), tetramethylpyrazine (TMP), and papaverine (Pap) on hemodynamics were compared in anesthetized rabbits. Three dosage levels (1.25, 2.5, 5 mg.kg-1, iv) were used for each agent. Sco lowered the blood pressure (BP), increased the cerebral blood flow (CBF) dose-dependently, but did not show significant influence on the femoral artery blood flow (FBF), the maximal decrease of BP, and the maximal increases of CBF being 15% and 20% of the control, respectively. In contrast, TMP raised the BP as well as increased the CBF and FBF simultaneously. Pap, however, lowered the BP, slightly increased the CBF and decreased the FBF only at large doses. The results suggested that Sco may cause a selective dilatation of cerebral blood vessels.