Alteration in Ca2+ availability involved in antigen-induced airway hyperresponsiveness in rats.
Alteration in Ca2+ availability involved in antigen-induced airway hyperresponsiveness in rats.
复制标题
Ca2 可用性的改变与抗原诱导的大鼠气道高反应性有关。
DOI：
10.1016/0014-2999(95)00132-5
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发表时间：
1995
影响因子：
5
通讯作者：
M. Misawa
中科院分区：
文献类型：
--
作者：
Y. Chiba;M. Misawa
本文探讨了在抗原激发诱导的气道高反应性中，Ca ~（2+）对乙酰胆碱诱导的支气管平滑肌收缩作用的增强作用的来源。在无Ca 2+（同时使用10− 6 M尼卡地平）条件下，气道高反应大鼠（0.15 ± 0.04 g）的支气管环对1 mM乙酰胆碱的收缩反应显著高于正常大鼠（0.02 ± 0.004 g; P < 0.05）。当肌肉用1 mM乙酰胆碱预处理时，在无钙溶液中，累积给予的Ca 2+诱导了具有高反应性气道的大鼠环中显著更大的支气管收缩（在存在10 - 6 M尼卡地平的情况下），而当肌肉用60 mM K+预处理时，两组之间未观察到显著差异。（存在10 - 6 M阿托品）。这些结果表明，从细胞内钙库释放和/或通过受体操纵的Ca ~（2+）通道流入气道平滑肌的Ca ~（2+）的可用性增加可能参与了大鼠气道对乙酰胆碱的高反应性。
The origin of Ca2+contributing to the enhancement of acetylcholine-induced bronchial smooth muscle constriction in airway hyperresponsiveness induced by antigen challenge was investigated. Under Ca2+-free (concomitant with 10−6M nicardipine) conditions, the contractile responses of bronchial rings to 1 mM acetylcholine were significantly greater in rings from rats with hyperresponsive airways (0.15 ± 0.04 g) than those of rings from normal rats (0.02 ± 0.004 g; P < 0.05). The cumulatively administered Ca2+induced a markedly greater bronchoconstriction in rings from rats with hyperresponsive airways in Ca2+-free solution when muscles were pretreated with 1 mM acetylcholine (in the presence of 10−6M nicardipine) than in rings from normal rats, whereas no significant difference in Ca2+-induced bronchoconstriction was observed between the two groups when muscles were pretreated with 60 mM K+(in the presence of 10−6M atropine). These findings suggest that enhancement of the availability of Ca2+released from intracellular stores and/or influxed through receptor-operated Ca2+channels in airway smooth muscles might be involved in the airway hyperresponsiveness to acetylcholine in rats.