Biochem/physiol Actions

S 38093 is an orally available compound with selective affinity toward histamine H3 receptor (human/mouse/rat H3R Ki = 0.2/1.44/8.8 μM), but not other histaminergic receptors, exhbiting both antagonist (KB = 652 nM against 300 nM (R)-A-Methylhistamine-induced GTPγS recruitment to mH3 CHO membrane; KB = 110 nM against 1 μM histamine-induced cAMP downregulation in hH3 CHO cells) and inverse agonist activity (hH3/rH3 HEK basal cAMP enhancing EC50 = 1.7/9 μM; 48% inhibition of ionomycin-induced hH3 or rH3 HEK AA reslease by 10 μM S 38093). S 38093 is reported to improve AD- and age-associated memory and cognition deficits in mice (0.1-3 mg/kg/day p.o.) and rats (0.1-10 mg/kg p.o. or i;p.), as well as display antiallodynic and antihyperalgesic efficacy in rat models of neuropathic pain in vivo.