Methacholine chloride

Acetyl-β-methylcholine is a muscarinic (M) receptor agonist.¹ In wild-type mice, acetyl-β-methylcholine decreases heart rate and blood pressure and increases the airway pressure time index, a measure of bronchoconstriction, in a dose-dependent manner. Cardiac and pulmonary responses are abolished in M₂ and M₃ knockout mice, respectively, suggesting that acetyl-β-methylcholine acts on cardiac M₂ and pulmonary M₃ receptors. Formulations containing acetyl-β-methylcholine have been used to diagnose asthma and to monitor response to asthma therapies.²

1.Fisher, J.T., Vincent, S.G., Gomeza, J., et al.Loss of vagally mediated bradycardia and bronchoconstriction in mice lacking M2 or M3 muscarinic acetylcholine receptorsFASEB J.18(67)711-713(2004) 2.Choi, S.H., Sheen, Y.H., Kim, M.A., et al.Clinical implications of oscillatory lung function during methacholine bronchoprovocation testing of preschool childrenBiomed. Res. Int.20171-9(2017)