Golovina V A, Blaustein M P
Department of Physiology and Center for Vascular Biology and Hypertension, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
Science. 1997 Mar 14;275(5306):1643-8. doi: 10.1126/science.275.5306.1643.
The organization of calcium (Ca2+) stores in the sarcoplasmic and endoplasmic reticulum (S-ER) is poorly understood. The dynamics of the storage and release of calcium in the S-ER of intact, cultured astrocytes and arterial myocytes were studied with high-resolution imaging methods. The S-ER appeared to be a continuous tubular network; nevertheless, calcium stores in the S-ER were organized into small, spatially distinct compartments that functioned as discrete units. Cyclopiazonic acid (an inhibitor of the calcium pump in the S-ER membrane) and caffeine or ryanodine unloaded different, spatially separate compartments. Heterogeneity of calcium stores was also revealed in cells activated by physiological agonists. These results suggest that cells can generate spatially and temporally distinct calcium signals to control individual calcium-dependent processes.
肌浆网和内质网（S-ER）中钙（Ca2+）储存的组织情况目前了解甚少。我们使用高分辨率成像方法研究了完整培养的星形胶质细胞和动脉肌细胞的S-ER中钙的储存和释放动态。S-ER似乎是一个连续的管状网络；然而，S-ER中的钙储存被组织成小的、空间上不同的隔室，这些隔室作为离散单元发挥作用。环匹阿尼酸（S-ER膜中钙泵的抑制剂）、咖啡因或ryanodine排空了不同的、空间上分离的隔室。在生理激动剂激活的细胞中也发现了钙储存的异质性。这些结果表明，细胞可以产生空间和时间上不同的钙信号，以控制个体的钙依赖性过程。
