Localization of a thrombin-sensitive calcium pool in platelets.
Electron microscopic x-ray microprobe analysis of pyroantimonate precipitates in platelets fixed in osmium tetroxide-pyroantimonate revealed calcium localization in the nucleoids of alpha-granules. This pool of calcium had largely disappeared within 10 sec after stimulation of platelets by thrombin. Such a rapid change suggests that this calcium pool may have a regulatory role in stimulus-response coupling.
D000818:Animals; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D002118:Calcium / Q000097:blood*; D002417:Cattle; D002467:Cell Nucleus / Q000378:metabolism / Q000648:ultrastructure; D006651:Histocytochemistry; D006801:Humans; D008722:Methods; D008854:Microscopy, Electron; D013917:Thrombin / Q000494:pharmacology*
D013917:Thrombin; D002118:Calcium