Metergoline

Metergoline is a serotonin (5-HT) receptor antagonist. It is active at 5-HT1 (pKi=7.8 for 5-HT1B), 5-HT2 (pKi=8.64, 8.75 and 8.75 for 5-HT2A, 5-HT2B and 5-HT2C respectively) and 5-HT7 (pKi=16 nM) receptor subtypes. Metergoline potently inhibits 5-HT radiolabeling of the human 5-hydroxytryptamine(7) receptor, with an IC₅₀ value of 73 nM. It inhibits 5-HT7 receptor-stimulated cAMP production with an IC₅₀ of 321 nM in HEK293 cells.