[3H]Mianserin: Differential Labeling of Serotonin2 and Histamine1 Receptors in Rat Brain1

Peroutka, Stephen J. and Solomon H. Snyder: [3H]Mianserin: branes. By using [3H]mianserin, both 5-HT2 and histamine H1 Differential labeling of serotonin2 and histamine1 receptors in receptors can be specifically labeled in rat cerebral cortex rat brain. J. Pharmacol. Exp. Ther. 21 6: 1 42-1 48, 1 981. membranes. Simultaneous incubation of brain membranes with 300 nM triprolidine or 30 nM spiroperidol enables the selective Mianserin, a tetracyclic antidepressant, is a potent serotonin labeling of 5-HT2 or histamine H1 receptors, respectively. In the (5-HT) and histamine H1 antagonist in peripheral smooth mus- guinea-pig cerebellum, [3H]mianserin exclusively labels hista-cle systems. Mianserin was found to possess high affinity for mine H1 receptors, since 5-HT2 sites are virtually absent in this 5-HT2 and histamine H1 receptor binding sites in brain mem- area. Mianserin is a tetracyclic piperazine derivative that was developed as an antiallergic compound (van der Burg et a!., 1970). In peripheral smooth muscle systems, it displays potent antiserotoninergic and antihistaminic activity as well as some a-adrenolytic effects (Vargaftig et a!., 1971). Mianserin is also a clinically effective antidepressant (Itil et a!., 1972; Fell et a!., 1973) despite relatively weak inhibition of norepinephrine an