Notes: BRL 54443 is a potent agonist of the serotonin (5-HT) receptor subtypes 5-HT1E and 5-HT1F (Ki values are 1.1 and 0.7 nM, respectively).{33346} It displays more than 30-fold selectivity over other 5-HT and dopamine receptors. At higher concentrations, BRL 54443 induces 5-HT2A-mediated contraction of mouse thoracic aorta strips in vitro (pEC50 = 6.5).{33347} It significantly reduces formalin-induced pain in rat hind paw.{33345}