Physiology of Airway Smooth Muscle Contraction: An Overview

Bronchial reactivity is a physiological property of healthy airways to develop a moderate airway obstruction in response to various non-specific stimuli, which is altered in several pulmonary diseases. The active effector of airway reactivity is airway smooth muscle (ASM). The contractile status of airway smooth muscle is under the control of many extracellular messengers acting on specific membrane receptors. Binding of the contractile messengers to their specific membrane receptors increases cytosolic Ca2+ concentration ([Ca2+]i). The shape of the resulting calcium signal is sensed by the contractile apparatus and hence determines the pattern of the contractile response. Agonists can also modify the sensitivity of the contractile apparatus to calcium, via phosphorylation and dephosphorylation of a network of regulatory proteins. These mechanisms can be altered in several respiratory diseases such and COPD, asthma, or exposure to air pollutants, leading to hyperreactivity, which can be pharmacologically controlled by drugs acting on the mechanisms of ASM contraction. The article describes the major intracellular mechanisms responsible for the excitation-contraction coupling in airway smooth muscle cell. *Corresponding author: Etienne Roux, University of Bordeaux, Adaptation Cardiovascular Ischemia, France, Tel: +33-5-57-89-01-05; E-mai l : [email protected] Received October 28, 2014; Accepted November 24, 2014; Published November 28, 2014 Citation: Ouedraogo N, Roux E (2014) Physiology of Airway Smooth Muscle Contraction: An Overview. J Pulm Respir Med 4: 221. doi:10.4172/2161105X.1000221 Copyright: © 2014 Ouedraogo N, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.