Acetyl-beta-methylcholine iodide

Methacholine iodide is a potent muscarinic-3 (M3) agonist. Methacholine iodide acts directly on acetylcholine receptors on smooth muscle causing bronchoconstriction and airway narrowing. Methacholine iodide shows a high sensitivity to identify bronchial hyperresponsiveness (BHR). Methacholine iodide can be used to measure airway hyperresponsiveness (AHR) as a diagnostic aid in the assessment of individuals with asthma-like symptoms and normal resting expiratory flow rates[1][2][3][4].

[1] Cohen J, et al. Relationship between airway responsiveness to neurokinin A and methacholine in asthma. Pulm Pharmacol Ther. 2005;18(3):171-176. DOI:10.1016/j.pupt.2004.11.008
[2] Anderson SD, et al. Comparison of mannitol and methacholine to predict exercise-induced bronchoconstriction and a clinical diagnosis of asthma. Respir Res. 2009;10(1):4. Published 2009 Jan 23. DOI:10.1186/1465-9921-10-4
[3] Cockcroft DW. Methacholine challenge methods. Chest. 2008;134(4):678-680. DOI:10.1378/chest.08-1306
[4] Kabara S, et al. Differential effects of thiopental on methacholine- and serotonin-induced bronchoconstriction in dogs. Br J Anaesth. 2003 Sep;91(3):379-84. DOI:10.1093/bja/aeg190
[5] Folkerts G, et al. Bradykinin causes inhibition of methacholine-induced bronchoconstriction in vivo in mice. Naunyn Schmiedebergs Arch Pharmacol. 2001 Jul;364(1):53-8. DOI:10.1007/s002100100430
[6] Vitorasso RL, et al. Methacholine dose response curve and acceptability criteria of respiratory mechanics modeling. Exp Lung Res. 2020 Feb-Mar;46(1-2):23-31. DOI:10.1080/01902148.2020.1711831