MDA-19 (also known as BZO-HEXOXIZID)[2][3] is a drug that acts as a potent and selective agonist for the cannabinoid receptorCB2, with reasonable selectivity over the psychoactive CB1 receptor, though with some variation between species. In animal studies it was effective for the treatment of neuropathic pain, but did not affect rat locomotor activity in that specific study. The pharmacology of MDA-19 in rat cannabinoid receptors have been demonstrated to function differently than human cannabinoid receptors with MDA-19 binding to human CB1 receptors 6.9× higher than rat CB1 receptors.[4][5]
^Diaz P, Xu J, Astruc-Diaz F, Pan HM, Brown DL, Naguib M (August 2008). "Design and Synthesis of a Novel Series of N-Alkyl Isatin Acylhydrazone Derivatives that Act as Selective Cannabinoid Receptor 2 Agonists for the Treatment of Neuropathic Pain". Journal of Medicinal Chemistry. 51 (16): 4932–4947. doi:10.1021/jm8002203. PMID18666769.