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

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 afte r injection (25% and 3-fold increase, respectively). Spectral analysis of t he 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 mi n (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 cau ses profound and long-lasting changes in the central integration of the sym pathetic baroreceptor-vasomotor reflex. (C) 2000 Elsevier Science B.V. All rights reserved.