Affinity of Serotonin Receptor Antagonists and Agonists to Recombinant and Native α1-Adrenoceptor Subtypes

[摘要] References(34)Cited-By(28)Binding affinities of serotonin (5-HT)-receptor antagonists and agonists at human recombinant α1-adrenoceptor subtypes (α1a-, α1b- and α1d-subtypes) were examined and compared with the functional affinities obtained in rat caudal artery (α1A-subtype), dog carotid artery (α1B-subtype) and rat thoracic aorta (α1D-subtype). Most of the 5-HT-receptor antagonists and agonists tested showed relatively high affinity to three α1-adrenoceptor subtypes. The highest affinity close to 1 nM was seen for NAN-190 (5-HT1A antagonist) in binding and functional studies. 5-Methylurapidil (5-HT1A agonist) and BMY7378 (5-HT1A agonist) showed, respectively, α1a(α1A)- or α1d(α1D)-subtype selectivity in both binding and functional affinities, but spiperone (5-HT2A antagonist) showed α1b-selectivity only in binding affinity. Functional affinity of ritanserin (5-HT2A antagonist) to the α1B-subtype was approximately 500-fold lower than that of affinity to the α1b-subtype. The present results show that many 5-HT-receptor antagonists and agonists have high affinity to α1-adrenoceptors, but suggest that there is deviation between their functional affinities and binding affinities for some drugs.

[学科分类] 药理学

[关键词] Serotonin receptor antagonist;Serotonin receptor agonist;α1-Adrenoceptor;Selectivity