title: Aequorin detects increased cytoplasmic calcium in platelets stimulated with phorbol ester or diacylglycerol.
abstract: A biochemical pathway to platelet activation involving protein kinase C has been deemed "Ca2+-independent", because the intracellular fluorophore quin2 indicates no rise in cytoplasmic [Ca2+] in platelets stimulated by certain agonists. However, unlike quin2, the Ca2+-sensitive photoprotein aequorin demonstrates a rise in [Ca2+] when platelet aggregation is induced by phorbol ester or diacylglycerol. Aequorin and quin2 appear to report different aspects of Ca2+ homeostasis, and the absence of a quin2 signal may not be sufficient to establish that a metabolic pathway is "Ca2+-independent".
mesh_terms: D000331:Aequorin; D000634:Aminoquinolines; D001792:Blood Platelets / Q000032:analysis*; D002118:Calcium / Q000097:blood*; D003593:Cytoplasm / Q000032:analysis; D004075:Diglycerides / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004533:Egtazic Acid / Q000494:pharmacology; D005989:Glycerides / Q000494:pharmacology*; D006801:Humans; D008164:Luminescent Proteins; D010704:Phorbols / Q000494:pharmacology*; D010974:Platelet Aggregation / Q000187:drug effects*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D000634:Aminoquinolines; D004075:Diglycerides; D005989:Glycerides; D008164:Luminescent Proteins; D010704:Phorbols; D000331:Aequorin; D004533:Egtazic Acid; C038237:1-oleoyl-2-acetylglycerol; D013755:Tetradecanoylphorbol Acetate; C035739:Quin2; D002118:Calcium