Mydriasis model in rats as a simple system to evaluate a2-Adrenergic activity of the imidazol(in)e compounds

Imidazol(in)e compounds show the diversity of pharmacological effects including mydriasis,hypotension,sedation,bradycardia and hypothermia. at first it was postulated that these effects are mediated via a2-adrenoceptors exclusively. clonidine is well known as a model agent to produce pupillary dilation in rats. however,it became obvious later that clonidine-like imidazol(in)e adrenoceptor agonists which produced mydriasis in rats,exhibit also a high affinity for imidazoline i1-receptors. that short report attempts to review the present status of studies to confirm that the mydriasis model in rats can be a selective system to evaluate the a2-adrenergic activity of potential pharmacologically active compounds of imidazol(in)e structure. copyright © 2013 by institute of pharmacology.