Quinpirole treatment increases renal sympathetic nerve activity and baroreflex gain in conscious rabbits: a spectral study

Abstract

Intravenous administration of 0.3 mg/kg of quinpirole to conscious rabbits that had been pretreated with domperidone caused a marked increase in blood pressure and renal sympathetic nerve activity with a peak at 5–10 min after injection (25% and 3-fold increase, respectively). Spectral analysis of the blood pressure–renal sympathetic nerve activity relationship in the 0.2–0.4 Hz domain showed that baroreflex gain was markedly increased at 5–10 min (4-fold) and at 20–25 min after injection (3.7-fold). These results show that administration of the dopamine D 2/D 3 receptor agonist quinpirole causes profound and long-lasting changes in the central integration of the sympathetic baroreceptor–vasomotor reflex.