COMPARATIVE BIOASSAY OF VASOACTIVE DRUGS USING ISOLATED PERFUSED RABBIT ARTERIES

A simple and reliable assay technique for vasoactive drugs is described. Using KCl-depolarised central artery preparations from the rabbit ear, and saphenous artery preparations from the hind leg, the following drugs were assayed for potency, rate of onset and duration of action (in inhibiting KCl-depolarisation-induced vasoconstriction): papaverine hydrochloride, cyclandelate (Cyclospasmol®), cinnarizine (Stugeron®), xanthinol niacinate (Complamin®) and dihydroergotoxine methanesulphonate - DEM - (Hydergin®). The effects of the drugs on the two types of preparation were similar. For the central artery, potency decreased in the order: cinnarizine > papaverine > DEM > cyclandelate > xanthinol niacinate, duration of action in the order: cinnarizine > cyclandelate > xanthinol niacinate > papaverine > DEM, and speed of onset of action in the order: DEM > papaverine > xanthinol niacinate > cyclandelate > cinnarizine. © 1969.