In:
Respiration, S. Karger AG, Vol. 66, No. 1 ( 1999), p. 59-64
Abstract:
〈 i 〉 Background: 〈 /i 〉 Endothelin (ET), a potent constrictor of smooth muscle including that of the airways, may contribute to the development of airway hyperresponsiveness. 〈 i 〉 Objective: 〈 /i 〉 To investigate the role of ET-1 on the airway smooth muscle, we examined the effects of ET-1 on the serotonin-induced contraction of guinea pig tracheal smooth muscle. 〈 i 〉 Methods: 〈 /i 〉 The changes in isometric tension evoked by serotonin were measured before and after the application of a subthreshold dose (a dose which did not induce smooth muscle contraction by itself) of ET-1. 〈 i 〉 Results: 〈 /i 〉 Serotonin caused smooth muscle contraction in a dose-dependent manner. The subthreshold doses of ET-1 (1 pM) and sarafotoxin 6c (1 pM), a selective ET 〈 sub 〉 B 〈 /sub 〉 receptor agonist, were found to potentiate significantly the contraction induced by serotonin. A potentiating effect of ET-1 was not altered by indomethacin or calphostin C, a protein kinase C inhibitor. 〈 i 〉 Conclusion: 〈 /i 〉 These results suggest that a subthreshold concentration of ET-1 can potentiate serotonin-induced contraction of smooth muscle through the activation of ET 〈 sub 〉 B 〈 /sub 〉 receptor, while in contrast cyclooxygenase and protein kinase C were found not to be involved in this mechanism.
Type of Medium:
Online Resource
ISSN:
0025-7931
,
1423-0356
Language:
English
Publisher:
S. Karger AG
Publication Date:
1999
detail.hit.zdb_id:
1464419-8
