Department of Chemistry, College of Science and Engineering, University of Minnesota, Minneapolis, Minnesota, USA.
Biophys J. 2011 Nov 16;101(10):2351-9. doi: 10.1016/j.bpj.2011.10.001. Epub 2011 Nov 15.
This study reports how quantal size, or the quantity of chemical messengers within a storage granule, is regulated in platelet dense-body granules via dynamic adaption of granule size according to changing levels of granule contents. Mechanistic studies using carbon-fiber microelectrode fast-scan cyclic voltammetry and amperometry methods correlated with transmission electron microscopy analysis reveal the impact of granule structural changes on granular content secretion kinetics and highlight the dynamic interplay between soluble granule contents and membrane components in exocytosis. Despite the distinct chemical profile of platelet dense-body granules, these secretory granules act according to general biochemical/biophysical phenomena using charge-charge interactions to sequester chemical messengers and employ known conserved exocytotic machinery to deliver them; therefore, the mechanistic information obtained herein further advances the general understanding of exocytosis while revealing fundamental details about blood platelets.
本研究报告了在血小板致密体颗粒中，通过根据颗粒内容物水平的变化动态调整颗粒大小来调节量子大小（即存储颗粒内化学信使的数量）的情况。使用碳纤维微电极快速扫描循环伏安法和安培法的机制研究与透射电子显微镜分析相关联，揭示了颗粒结构变化对颗粒内容物分泌动力学的影响，并强调了在胞吐作用中可溶性颗粒内容物和膜成分之间的动态相互作用。尽管血小板致密体颗粒具有独特的化学特征，但这些分泌颗粒根据一般的生化/生物物理现象发挥作用，利用电荷-电荷相互作用来隔离化学信使，并采用已知的保守胞吐机制来传递它们；因此，本文获得的机制信息进一步推进了对胞吐作用的普遍理解，同时揭示了关于血小板的基本细节。
