Middleton E
Eur J Respir Dis Suppl. 1983;128 (Pt 1):123-32.
Airway caliber is primarily under the control of cholinergically innervated smooth muscle but it is also effected in pathological states by the tissue effects of chemical mediators released from mast cells, the hypersecretion of mucous glands, and the aggravation of airway narrowing by the vagus-mediated bronchoconstrictor reflex, and also by the ingress of inflammatory cells into the bronchial wall. The function of each of these cell types (smooth muscle, mast cells, mucous glands, vagus nerve, and inflammatory cells) is dependent upon Ca2+ ions. That is, agonist-induced smooth muscle contraction, antigen-induced mediator release from mast cells, mucous gland secretion, vagus nerve impulse initiation and conduction, and the movement of inflammatory cells are all Ca2+-dependent phenomena in which Ca2+ serves as the coupling agent between excitation and contraction and stimulus and secretion. Normally, all cells in the body maintain a very high inside-to-outside Ca2+ concentration gradient, the maintenance of which involves several mechanisms that pump calcium out of the cell. Calcium antagonists may inhibit the ingress of Ca2+ ions from the extracellular environment or may influence the availability of calcium ions from plasma membrane or subcellular organelles. Calcium antagonists have been shown to exert a beneficial effect in exercise-induced asthma and may possibly affect the release of chemical mediators from mast cells. The future of calcium antagonist therapy in the management of asthma remains to be determined.
气道管径主要受胆碱能神经支配的平滑肌控制，但在病理状态下，它也会受到肥大细胞释放的化学介质的组织效应、黏液腺分泌亢进、迷走神经介导的支气管收缩反射导致的气道狭窄加重以及炎症细胞进入支气管壁的影响。这些细胞类型（平滑肌、肥大细胞、黏液腺、迷走神经和炎症细胞）中的每一种功能都依赖于钙离子。也就是说，激动剂诱导的平滑肌收缩、抗原诱导的肥大细胞介质释放、黏液腺分泌、迷走神经冲动的起始和传导以及炎症细胞的运动都是依赖钙离子的现象，其中钙离子充当兴奋与收缩、刺激与分泌之间的偶联剂。正常情况下，体内所有细胞都维持着非常高的细胞内与细胞外钙离子浓度梯度，其维持涉及多种将钙离子泵出细胞的机制。钙拮抗剂可能会抑制细胞外环境中钙离子的进入，或者可能会影响质膜或亚细胞器中钙离子的可用性。钙拮抗剂已被证明在运动性哮喘中发挥有益作用，并且可能会影响肥大细胞化学介质的释放。钙拮抗剂治疗哮喘的未来仍有待确定。
