Title

Regulation of airway smooth muscle cell contractility by Ca2+ signaling and sensitivity

UMMS Affiliation

Department of Physiology; University of Massachusetts Medical School Worcester

Publication Date

12-21-2007

Document Type

Article

Subjects

Animals; Asthma; Calcium Channels; Calcium Signaling; Humans; Inositol 1,4,5-Trisphosphate Receptors; Membrane Potentials; Muscle Contraction; Muscle Relaxation; Muscle, Smooth; Ryanodine Receptor Calcium Release Channel

Disciplines

Life Sciences | Medicine and Health Sciences

Abstract

Airway smooth muscle cell contraction is regulated by changes in intracellular Ca2+ concentration ([Ca2+]i) and the responsiveness of the airway smooth muscle cell to this Ca2+. The mechanism controlling [Ca2+]i primarily involves agonist-induced release of Ca2+ from internal stores to generate Ca2+ oscillations. The extent of contraction correlates with the persistence and frequency of these Ca2+ oscillations. The maintenance of the Ca2+ oscillations requires Ca2+ influx, but membrane depolarization appears to have a minor role in initiating or sustaining contraction. Contraction also requires agonist-induced Ca2+ sensitization, which is mediated mainly by decreases in myosin light-chain phosphatase activity. Although it is not clear if airway hyperresponsiveness associated with asthma results from the specific modulation of these Ca2+-based regulatory mechanisms, bronchodilators relax airways by both attenuating the Ca2+ oscillations and by decreasing the Ca2+ sensitivity.

Rights and Permissions

Citation: Proc Am Thorac Soc. 2008 Jan 1;5(1):23-31. Link to article on publisher's site

DOI of Published Version

10.1513/pats.200704-050VS

Related Resources

Link to Article in PubMed

Journal/Book/Conference Title

Proceedings of the American Thoracic Society

PubMed ID

18094081