Quantitative Measurement of Binding Sites and Washout Components for Calcium Ion in Vascular Smooth Muscle
Quantitative Measurement of Binding Sites and Washout Components for Calcium Ion in Vascular Smooth Muscle
复制标题
血管平滑肌钙离子结合位点和冲洗成分的定量测定
DOI：
--
复制
发表时间：
1978
期刊：
影响因子：
--
通讯作者：
G. B. Weiss
中科院分区：
文献类型：
--
作者：
G. B. Weiss
在最近的一篇综述文章(Weiss，1977a)中，提出了一个普遍的假设，即钙离子对于全面了解肌肉系统对药物的反应性的核心重要性。简而言之，这一观点认为，肌肉对给定制剂的定性和定量反应都直接由细胞内可用钙的量决定，而这反过来又是每种特定类型肌肉中存在的特定细胞结构的不同钙结合特性的直接结果。这并不是说，从药物-受体相互作用开始的序列的其他阶段也不是必不可少的。然而，最终反应的性质的确定不是受体激活的函数，而是膜结合和通透性特征变化的结果，最终是细胞内钙水平的直接函数。尽管这种关系存在于所有类型的肌肉中，但对肌肉张力与钙分布和运动之间的相关性的阐述在平滑肌肉中没有像在横纹肌中那样迅速。在横纹肌中，从膜兴奋到肌肉收缩的一系列事件已经被令人信服地记录下来(见Sandow，1965；Bianci，1968)，并与明确定义的形态结构有关。然而，在平滑肌中，与横纹肌中观察到的结构相似的解剖结构并不容易识别，部分原因是，无法以平行的方式描述特定的细胞来源和钙离子的位置。
In a recent review article (Weiss, 1977a), a general hypothesis was developed concerning the central importance of Ca2+ to any comprehensive understanding of responsiveness of muscle systems to pharmacological agents. Briefly, this view was that both the qualitative and the quantitative nature of the muscle response to a given agent is directly determined by the amounts of intracellular Ca2+ available and this, in turn, is a direct consequence of differing Ca2+-binding properties of the specific cytoarchitecture present in each particular type of muscle. This is not to say that other phases of the sequence beginning with the drug-receptor interaction are not also essential. However, determination of the nature of the final response obtained is not a function of receptor activation but, rather, a result of alterations in membrane binding and permeability characteristics and, ultimately, a direct function of the intracellular Ca2+ level. Though this relationship exists in all types of muscle, elaboration of correlations between muscle tension and Ca2+ distribution and movements has not progressed as rapidly in smooth muscle as in striated muscle. The sequence of events leading from membrane excitation to muscle contraction in striated muscle has been convincingly documented (see Sandow, 1965; Bianchi, 1968) and related to clearly defined morphological structures. However, in smooth muscle anatomical structures resembling those observed in striated muscle are not as readily identified and, partly as a consequence of this, specific cellular sources and sites for Ca2+ cannot be delineated in a parallel fashion.