Selectivity of some ergot derivatives for 5-HT1 and 5-HT2 receptors of rat cerebral cortex.
The affinities of several ergot derivatives for 5-HT1 and 5-HT2 receptors were evaluated using [3H]5-HT and [3H]mianserin, and membranes prepared from rat frontal cortex. CQ 32-084, which had a Ki value against the 5-HT2 component of [3H]mianserin binding of 9 nM, had little effect on [3H]5-HT binding and was selective for the 5-HT2 receptor. Lisuride and LY-158A also displayed preferential affinity for the 5-HT2 receptor. Dihydroergocryptine, CM 29-712, lergotrile and LY-062 were more selective for the 5-HT1 receptor. Bromocriptine showed little selectivity for either subtype. Overall, the ergot derivatives displayed markedly different affinities and selectivities for central 5-HT receptors suggesting that their serotonergic actions should be considered when evaluating their pharmacological spectrum of activity.
D000818:Animals; D002540:Cerebral Cortex / Q000187:drug effects*; D004873:Ergolines / Q000494:pharmacology; D004876:Ergot Alkaloids / Q000494:pharmacology*; D005260:Female; D008297:Male; D008803:Mianserin / Q000378:metabolism; D019257:Quinpirole; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000187:drug effects*; D012701:Serotonin / Q000378:metabolism; D013329:Structure-Activity Relationship
D004873:Ergolines; D004876:Ergot Alkaloids; D011985:Receptors, Serotonin; D019257:Quinpirole; D008803:Mianserin; C031648:etisulergine; D012701:Serotonin