Effects of moxonidine on corticocerebral blood flow under normal and ischemic conditions in conscious rabbits

Hypertension associated with excessive liberation of circulating and tissue catecholamines is an independent risk factor for further cardiovascular co mplications and an important predictor of stroke. Moxonidine is a centrally acting antihypertensive drug with potent action on I-1-imidazoline recepto rs. It inhibits catecholamine release and is therefore expected to exert an antiadrenergic effect at various levels in the regulation of the cardiovas cular system. The aim of this study was to investigate the effect of moxoni dine (0.025-0.1 mg/kg, i.v.) on the normal and unilateral carotid occlusion -induced impaired corticocerebral blood flow (cCBF) determined by hydrogen polarography, on mean arterial blood pressure (MABP) and heart rate (HR) in conscious rabbits. Moxonidine produced a reduction of MABP and HR. On the other hand, after administration of the drug, a significant increase in the normal and impaired cCBF was observed. Because the improvement in cCBF was conspicuous in both normal and ischemic conditions, moxonidine might be be neficial not only in the treatment of hypertension but also in the manageme nt of cerebral ischemia.