The effects of superoxide anion on intracellular Ca~(2+) concentration and contractility in cultured bovine aortic smooth muscle cells
- VernacularTitle:超氧阴离子对培养的牛动脉平滑肌细胞内钙及收缩性的影响
- Author:
Wei CHENG
;
Zhi LI
;
Koyama TETSUYA
;
Oike MASAHIRO
;
Ito YUSHI
- Publication Type:Journal Article
- Keywords:
calcium;
vascular smooth muscle;
cultured cells;
aorta;
xanthine oxidase;
adenosine triphosphate
- From:
Chinese Pharmacological Bulletin
1987;0(02):-
- CountryChina
- Language:Chinese
-
Abstract:
AIM To study the effects of superox- ide anion (O ) on Ca2+ homeostasi and contractility in cultured bovine aortic smooth muscle cell. METHODS Using Fura-2 fluorescence technique to determine Ca2+ level and collagen gel contraction system to analyze muscle contractility. RESULTS ATP (10 ?mol? L-1 )-induced Ca2+ transient was smaller in xanthine oxidase treated cells(X/XO) than control. The mean peak increment of [Ca2+ ]i (△[Ca2+ ], peak) and the time integral of the elevated [Ca2+ ], (∫ △[Ca2+ ]i dt) for 5 min were decreased from (206. 1 ? 10.2) to (147.4 ? 14.7) nmol? L-1, and from (12.2 ?0.5) to (9.8 ? 0.8) ?mol?L-1 .s-1. △ [Ca2+ ], peak induced by thapsigargin(1 ?mol. L- 1 ) in Ca2+ -free solution was not affected by X/XO, but was decreased from (27. 3 ? 1 .0) nmol? L-l to (13 .5 ? 1 .0 ) nmol? L- 1 in Ca2+ -containing solution be cause of the activation of CRAC(△[Ca2+ ], CRAC). X/XO accelerated the velocity of thapsigargin-induced Ca2+ leak from (78.7 ? 3.4) s to (64.8 ? 4.40) s. Gel contraction area in X/XO-treated cells induced by ATP or thapsigargin (in Ca2+ free solution and in Krebs solution) was decreased from 23.6% ? 4.6% to 7.4% ?0.2%, from 3.5% ?0.6% to - l.0% ? 0.5%, and from 7.9% ? l.4% to - 0.5% ? 0.7%, respectively. CONCLUTION O2- attenuats smooth muscle contraction by impairing some of Ca2+ mobilization pathways.