PT - JOURNAL ARTICLE AU - Wainscott, D B AU - Lucaites, V L AU - Kursar, J D AU - Baez, M AU - Nelson, D L TI - Pharmacologic characterization of the human 5-hydroxytryptamine2B receptor: evidence for species differences. DP - 1996 Feb 01 TA - Journal of Pharmacology and Experimental Therapeutics PG - 720--727 VI - 276 IP - 2 4099 - http://jpet.aspetjournals.org/content/276/2/720.short 4100 - http://jpet.aspetjournals.org/content/276/2/720.full SO - J Pharmacol Exp Ther1996 Feb 01; 276 AB - The 5-Hydroxytryptamine2B (5-HT2B) receptor was cloned originally from rat stomach fundus and its pharmacology was determined to be consistent with that of the receptor responsible for contraction of rat fundal tissue in response to 5-HT. Recently, the cloning of the human homolog of the 5-HT2B receptor has been reported and, in this study, we report a detailed pharmacological characterization of this human receptor. The cloned human 5-HT2B receptor has high affinity for [3H]5-HT (Kd = 10.6 +/- 1.5 nM), and the pharmacology of this receptor matches closely the rat 5-HT2B receptor, consistent with the structural relatedness of these two proteins. Most compounds tested show no difference in affinity for the human or rat receptors. There were, however, groups of compounds that discriminated between the human and rat 5-HT2B receptors. Examples include certain ergolines such as methysergide and mesulergine, which have higher affinity for the human than for the rat receptor. Similarly, certain benzoylpiperidines, e.g., ketanserin, pirenperone and pipamperone, and the antipsychotics clozapine and olanzapine have higher affinity for the human 5-HT2B receptor. These pharmacological findings reinforce the desirability of having the human forms of receptors when considering drug actions.