High-throughput assessment identifying major platelet Ca2+ entry pathways via tyrosine kinase-linked and G protein-coupled receptors

•In a well-plate based assay, a systematic comparison was made of cytosolic Ca2+ traces in platelets in the presence or absence of extracellular CaCl2, allowing the construction of Ca2+ entry ratio curves.•The Ca2+ entry ratios depended on the agonist strength and type, and were enforced by secondary mediators.•Upon blockage of SERCAs, Ca2+ entry ratios increased to up to 300, i.e. more with collagen-receptor than with thrombin-receptor stimulation.•Pharmacological evidence pointed to ORAI1 and sodium-calcium exchange as dominate Ca2+ entry carriers, independent of agonist type, with an initial role of P2X1 channels.