Calcium Signalling in Platelets and Other Cells

Reviewed are new concepts and models of Ca2+ signalling originating from work with various animal cells, as well as the applicability of these models to the signalling systems used by blood platelets. The following processes and mechanisms are discussed: Ca2+ oscillations and waves; Ca2+ -induced Ca2+ release; involvement of InsP3-receptors and quanta1 release of Ca2+; different pathways of phospholipase C activation; heterogeneity in the intracellular Ca2+ stores; store-and receptor-regulated Ca2+ entry. Additionally, some typical aspects of Ca2+ signalling in platelets are reviewed: involvement of protein serine/threonine and tyrosine kinases in the regulation of signal transduction; possible functions of platelet glycoproteins; and the importance of Ca2+ for the exocytotic and procoagulant responses.