N-Desmethylclozapine-d8 is intended for use as an internal standard for the quantification of N-desmethylclozapine by GC- or LC-MS. N-Desmethylclozapine is an active metabolite of the atypical antipsychotic clozapine .1 It was originally described as an antagonist of serotonin (5-HT) receptor subtype 5-HT2C (IC50 = 7.1 nM in rat choroid plexus) and later as an inverse agonist using human recombinant receptors.2,3 N-Desmethylclozapine is an antagonist at dopamine D4 receptors, an agonist at δ-opioid receptors, and a partial agonist at dopamine D2 and D3, M1 muscarinic acetylcholine, and 5-HT1A receptors.3,1,4 N-Desmethylclozapine (30 mg/kg) decreases exploratory locomotor activity and increases prepulse inhibiton of the acoustic startle response in mice.5
1.Burstein, E.S., Ma, J., Wong, S., et al.Intrinsic efficacy of antipsychotics at human D2, D3, and D4 dopamine receptors: Identification of the clozapine metabolite N-desmethylclozapine as a D2/D3 partial agonistJ. Pharmacol. Exp. Ther.315(3)1278-1287(2005) 2.KuoppamÄki, M., SyvÄlahti, E., and Hietala, J.Clozapine and N-desmethylclozapine are potent 5-HT1C receptor antagonistsEur. J. Pharmacol.245(2)179-182(1993) 3.Lameh, J., Burstein, E.S., Taylor, E., et al.Pharmacology of N-desmethylclozapinePharmacol. Ther.115(2)223-231(2007) 4.Odagaki, Y., Kinoshita, M., and Ota, T.Comparative analysis of pharmacological properties of xanomeline and N-desmethylclozapine in rat brain membranesJ. Psychopharmacol.30(9)896-912(2016) 5.Maehara, S., Hikichi, H., and Ohta, H.Behavioral effects of N-desmethylclozapine on locomotor activity and sensorimotor gating function in mice-Possible involvement of muscarinic receptorsBrain Res.1418111-119(2011)