AM1241 is a cannabinoid (CB) receptor agonist that is selective for CB2 over CB1 with Ki values of 7.1 and 580 nM for human recombinant receptors transfected into HEK and CHO cells, respectively, in a radioligand binding assay. It is considered a protean agonist as it has neutral antagonist and partial agonist activity, depending on the assay utilized. It is also acts in a species-dependent manner in vitro, acting as an agonist at human CB2 receptors (EC50 = 190 nM) but an inverse agonist at rat and mouse CB2 receptors (EC50s = 216 and 463 nM, respectively). AM1241 produces antinociception to thermal stimuli in rat hindpaw. The antinociceptive actions of AM1241 were blocked by the CB2 receptor-selective antagonist AM630 but not by the CB1 receptor-selective antagonist AM251 . AM1241 is neuroprotective, preventing HIV-1 glycoprotein Gp120-induced apoptosis in primary human and murine neural progenitor cells and increasing cell survival and differentiation. It increases hippocampal neurogenesis and decreases astro- and gliogenesis in GFAP/Gp120 transgenic mice when administered at a dose of 10 mg/kg daily for ten days. AM1241 also delays motor impairment in a murine model of amytrophic lateral sclerosis (ALS).
AM1241 acts as an antinociceptive agent in several animal pain models. It has a potential to delay disease progression in amyotrophic lateral sclerosis (ALS) mouse model. Intrathecal, intravenous or intraperitoneal administration of AM1241 reduces hyperalgesia and allodynia in neuropathic rats.
