N-Desmethyl Pirenzepine-d8 is a deuterium-labeled metabolite of Pirenzepine (sc-204197). Pirenzepine is a selective antagonist for the M1 muscarinic receptor (mAChR) and is reported to block presynaptic M1 receptors as well as some reported inverse agonist activity. A study investigating the pharmacological characterization of the muscarinic receptors associated with ACh-induced pulmonary vasodilation in a rabbit model of pulmonary hypertension determined the IC|50|to be 2.51x10|-7|M. Additional research studies have investigated the role of Pirenzepine in the pathophysiology of myopia. Other M1 receptor antagonists offered include Telenzepine (sc-204332). N-Desmethyl Pirenzepine-d8is a deuterium-labeled metabolite of Pirenzepine