1992 Volume 59 Issue 4 Pages 457-459
The selectivity of tizanidine to the imidazoline-receptor and α2-adrenoceptor recognized by 3H-p-aminoclonidine was examined in rat kidney membranes and was compared with those of other imidazoline compounds. Tizanidine bound to the imidazoline-receptors with approximately 20 times higher affinity than the α2-adrenoceptors. The order of relative selectivity to imidazoline receptor was tizanidine > oxymetazoline > clonidine > naphazoline, where clonidine showed an equal affinity to both receptors. Tizanidine may act more potently on the imidazoline-receptors than the α2-adrenoceptors.