Effects of Intraventricular 6-Hydroxydopamine on Cerebrovascular CO2Reactivity in Anesthetized Rats

Abstract

Regional cerebral blood flow was measured by the ¹⁴C‐ethanol technique in anesthetized rats before and after intraventricular injection of 6‐hydroxydopamine. This treatment reduced the fluorescence of the central noradrenaline and dopamine nerve terminals, as well as of the perivascular nerve terminals in cerebral vessels. The administration of 6‐hydroxydopamine had no significant effect on cerebral blood flow at normocapnia. The cerebrovascular reactivity to hypercapnia was significantly increased in the 6‐hydroxydopamine treated animals. The results indicate an involvement of central catecholamine pathways in the cerebrovascular reactivity to hypercapnia.