Marthan R, Savineau J P, Mironneau J
Respir Physiol. 1987 Feb;67(2):127-35. doi: 10.1016/0034-5687(87)90035-1.
The aim of this study was to investigate the role played by an intracellular calcium store in human bronchoconstriction. Human isolated bronchial smooth muscle strips (5-6 mm long, 0.4-0.5 mm wide) were taken from lung specimens during pneumonectomy. Isometric contraction was recorded after stimulation by 10(-4) M acetylcholine in physiological solutions. The amplitude of acetylcholine-induced contractions was measured in the presence and absence of calcium ions in the perfusing medium. When the perfusing medium was switched to a calcium-free solution the amplitude of the acetylcholine-induced contraction was measured with respect to the duration of calcium-free perfusion. The amplitude of the contraction was 82.1 +/- 11.3%, 77.2 +/- 15.4%, 63 +/- 10.6% of the maximum contraction after the strips were perfused in calcium-free solutions for 1, 3 and 5 min respectively. Several successive contractions could be elicited, and even after 20 min of calcium-free perfusion, acetylcholine was still able to elicit contractions. These results suggest that an intracellular calcium store may be involved in human bronchoconstriction. This finding may help further our understanding of the effects of calcium antagonists on human airways.
本研究的目的是探讨细胞内钙库在人类支气管收缩中所起的作用。从肺切除术中获取的肺标本中取出人离体支气管平滑肌条（长5 - 6毫米，宽0.4 - 0.5毫米）。在生理溶液中用10⁻⁴M乙酰胆碱刺激后记录等长收缩。在灌注介质中存在和不存在钙离子的情况下测量乙酰胆碱诱导的收缩幅度。当灌注介质切换到无钙溶液时，测量乙酰胆碱诱导的收缩幅度相对于无钙灌注持续时间的变化。在分别无钙溶液灌注1、3和5分钟后，收缩幅度分别为最大收缩幅度的82.1±11.3%、77.2±15.4%、63±10.6%。可以引发几次连续的收缩，甚至在无钙灌注20分钟后，乙酰胆碱仍能引发收缩。这些结果表明细胞内钙库可能参与人类支气管收缩。这一发现可能有助于我们进一步了解钙拮抗剂对人类气道的作用。
