LP44 is a full agonist of the serotonin 5-HT7 receptor (Ki = 0.22 nM) that displays 200- and greater than 1,000-fold selectivity over 5-HT1A (Ki = 52.7 nM) and 5-HT2A (Ki = 326 nM) receptors, respectively.1 It can induce relaxation of substance P-induced guinea pig ileum contraction with an EC50 value of 2.56 μM.[1]
Reference:
[1]. Leopoldo, M., Berardi, F., Colabufo, N.A., et al. Structure-affinity relationship study on N-(1,2,3,4-tetrahydronaphthalen-1-yl)-4-aryl-1-piperazinealkylamides, a new class of 5-hydroxytryptamine7 receptor agents. J.Med.Chem 47, 6616-6624 (2004).