CALCIUM TRANSIENTS IN STRIATED MUSCLE AND OTHER CELLS

钙敏感生物发光蛋白水母发光蛋白及相关 光蛋白将被用于研究细胞内的调节 蛙骨骼肌、蛙肌和蛙肌中Ca~（++）浓度 哺乳动物的心肌 结果将在一些比较 与那些获得钙选择性微环境， 个电极 高增益显微图像增强， 计算机图像处理将用于定位Ca ++在 注射水母发光蛋白的细胞。 将作出重大努力， 水母发光蛋白和其他发光蛋白的同种，并研究 其动力学和Ca ++敏感性。 特别强调， 对心肌的研究将给予分析， 通过改变肌原纤维对Ca ++的反应性， 心脏对正性肌力干预的反应，特别是 对α-肾上腺素受体刺激的反应。 系统分析 也将进行的因素负责改建 在肌肉长度变化后的Ca ++瞬变中， 收缩频率 在骨骼肌中， 计划对肌醇 三磷酸盐的释放主要涉及 激发：收缩偶联。

The calcium-sensitive bioluminescent protein aequorin and related photoproteins will be used to study the regulation of intracellular Ca++ concentration in frog skeletal muscle, and in frog and mammalian cardiac muscle. Results will be compared in some circumstances with those obtained with calcium-selective micro- electrodes. High-gain microscopic image intensification with computer image processing will be used to localize Ca++ in aequorin-injected cells. A major effort will be mounted to resolve the isospecies of aequorin and other photoproteins, and to study their kinetics and Ca++-sensitivity. Particular emphasis in the studies on cardiac muscle will be given to the analysis of the role played by changes in myofibrillar responsiveness to Ca++ in responses of the heart to inotropic interventions, particularly the response to alpha-adrenoceptor stimulation. Systematic analysis will also be carried out of the factors responsible for alterations in the Ca++ transient after changes in muscle length and contraction frequency. In skeletal muscle a variety of experiments are planned to critically test the hypothesis that inositol triphosphate release is centrally involved in excitation:contraction coupling.