Importance of imidazoline-preferring receptors in the cardiovascular actions of chronically administered moxonidine, rilmenidine and clonidine in conscious rabbits

Abstract

The greater effect of efaroxan compared to the alpha(2)-adrenoceptor antagonist 2-MI suggests that the hypotension induced by chronic subcutaneous administration of moxonidine, rilmenidine and clonidine is mediated predominantly via an action on central imidazoline receptors. Furthermore, all agents showed a propensity to produce rebound hypertension with imidazoline receptor blockade. However, only clonidine showed a rebound phenomenon when challenged by acute central alpha(2)-adrenoceptor blockade

Cardiac and renal baroreflex control during stress in conscious renovascular hypertensive rabbits: effect of rilmenidine

“…The dose was chosen to give a near maximum effect based on earlier dose-response studies with chronic administration to normotensive animals [29]. Control RSNA and HR baroreflexes were evoked as described earlier.…”

Actions of rilmenidine on neurogenic hypertension in BPH/2J genetically hypertensive mice

“…We conclude that hypertension in BPH/2J is likely to arise from sympathetic activity driven from regions other than the RVLM. Previous studies have shown that vagal excitatory effects become less prominent with chronic treatment [27,41] likely due to central a 2 -adrenoceptors desensitization [38]. Thus, to avoid these and other acute effects on the heart [18], as well as other peripheral actions of rilmenidine [42], the main focus of the present study involved determining the central sympatholytic hypotensive effects by central infusion of rilmenidine.…”

Comparison in Conscious Rabbits of the Baroreceptor-Heart Rate Reflex Effects of Chronic Treatment with Rilmenidine, Moxonidine, and Clonidine

“…These doses were effective chronically as determined previously (Parkin et al, 2003). Moxonidine infusions were directly preceded by an initial 280 μg/kg intravenous bolus due to its slow onset of action.…”