Title

Airway contractility and smooth muscle Ca(2+) signaling in lung slices from different mouse strains

UMMS Affiliation

Department of Physiology

Date

6-5-2003

Document Type

Article

Subjects

Acetylcholine; Anesthetics, Inhalation; Animals; Calcium Signaling; Cells, Cultured; Halothane; Lung; Mice; Mice, Inbred A; Mice, Inbred BALB C; Mice, Inbred C3H; Microscopy, Confocal; Muscle Contraction; Muscle, Smooth; Species Specificity; Vasodilator Agents

Disciplines

Life Sciences | Medicine and Health Sciences

Abstract

To investigate the hypothesis that altered Ca2+ signaling in airway smooth muscle cells (SMCs) is responsible for airway hyperreactivity, we compared, with the use of confocal and phase-contrast microscopy, the airway contractility and Ca2+ changes in SMCs induced by acetylcholine (ACh) in lung slices from different mouse strains (A/J, Balb/C, and C3H/ HeJ). The airways from each mouse strain displayed a concentration-dependent contraction to ACh. The contractile response of the airways of the C3H/HeJ mice was found, in contrast to earlier studies, to be much greater and faster than that of A/J and Balb/C mice. This difference in airway reactivity can be, in part, attributable to halothane, a volatile anesthetic that was previously used during in vivo measurements of airway reactivity but found here to significantly alter the ACh contractile response of airways in lung slices. The ACh-induced Ca2+ response of the airway SMCs in all of the various mouse strains was also concentration dependent. The magnitude of the initial Ca2+ increase and the frequency of the subsequent Ca2+ oscillations induced by ACh increased with ACh concentration. However, no differences in the Ca2+ responses to ACh could be distinguished between the mouse strains. These results suggest that the mechanism responsible for airway hyperreactivity in different mouse strains resides with the Ca2+ sensitivity of the contractile apparatus of the SMCs rather than with the Ca2+ signaling itself.

Rights and Permissions

Citation: J Appl Physiol. 2003 Sep;95(3):1325-32; discussion 1314. Epub 2003 May 30. Link to article on publisher's site

Related Resources

Link to Article in PubMed

Journal Title

Journal of applied physiology (Bethesda, Md. : 1985)

PubMed ID

12777405