Cytosolic calcium in platelet activation

Experiments with permeabilised platelets, and with intact platelets loaded with fluorescent Ca²⁺-indicators, over the past several years have greatly extended our knowledge and understanding of cytosolic Ca²⁺ as a platelet activator and its interactions with other cytosolic regulators. This article outlines insights, gained from the use of the fluorescent dyes, into maintenance and restoration of basal Ca²⁺]_i, mechanisms of receptor-mediated Ca²⁺-mobilisation and quantitation of Ca²⁺]_i/response relations in intact human platelets.