Gene regulation of muscarinic receptor subtypes

摘要: Of the five cloned muscarinic receptor subtypes, human airways express only three subtypes (M1, M2 and M3) these are differentially distributed in [1]. M1-receptors localised to alveolar walls, parasympathetic ganglia submucosal glands, whereas M3-receptors predominant airway smooth muscle glands. In contrast, M2-receptors of small airways, although there is little evidence that receptors play an important functional role regulation tone, at least airways. Functional studies suggest regulating release acetylcholine from nerves which inhibit cholinergic neural contraction have been demonstrated vitro pre-junctional animal [2,4]. There considerable may be dysfunctional patients with asthma this might contribute exaggerated reflex bronchoconstriction [4]. several possible mechanisms result dysfunction M2-receptors, including viral infections, eosinophil basic proteins oxidants. The inflammatory process also impaired function M2-receptors.