Platelets playa fundamental, life-saving role in hemostasis and blood clotting at sites of vascular injury. Unwanted platelet activation and arterial thombus formation are, however, implicated in the onset of myocardial infarction, stroke, and other cardiovascular diseases. Acceptance that platelets play a major role in the pathogenesis of atherosclerosis including coronary heart disease has revolutionized the pharmacological treatment of cardiovascular diseases, and aspirin is now an essential antiplatelet drug and the golden standard for future developments. Yet the search for better and perhaps safer antiplatelet drugs is one of the most active areas of investigation in both basic and clinical research. Platelets, especially human platelets, have also emerged as one of the major models for the study of inter- and intracellular signal transduction pathways. Many biochemists, cell biologists, pharmacologists, pathologists, hematologists, and cardiologists find platelets useful for studying processes such as adhesion, inside-out and outside-in signalling through the plasma membrane, channels, calcium homeostasis, protein kinases, the network of intracellular signal transduction cascades, and the release of vasoactive substances. The aim of the editors has been to compile chapters summarizing the current state-of-the-art information on the biochemistry, cell biology, pharmacology, and physiologic and pathophysiologic roles of human platelets. We hope that this volume represents the major aspects of current platelet research although it is perhaps inevitable that certain areas are covered less thoroughly than others. We would like to acknowledge the excellent help and support of the Springer-Verlag staff, in particular that of Ms. Doris Walker.

Section I: Platelet Development, Morphology and Physiology

1 Megakaryocytopoiesis: The Megakaryocyte/Platelet Haemostatic Axis
2 Human Platelet Morphology/Ultrastructure
3 Platelet Adhesion
4 Platelet Aggregation
Section II: Platelet Biochemistry, Signal Transduction
5 Platelet Receptors: The Thrombin Receptor
6 Platelet ADP/Purinergic Receptors
7 Platelet Prostaglandin Receptors
8 Platelet Adhesion and Aggregation Receptors
9 Platelet G Proteins and Adenylyl and Guanylyl Cyclases
10 Platelet Phosphodiesterases
11 Platelet Phospholipases C and D
12 Protein Kinase C and Its Interactions with Other Serine-Threonine Kinases
13 Platelet Protein Tyrosine Kinases
14 Protein Phosphatases in Platelet Function
15 Ca2+ Homeostasis in Human Platelets
16 Regulation of Platelet Function by Nitric Oxide and Other Nitrogen- and Oxygen-Derived Reactive Species
17 Platelet 5-Hydroxytryptamine Transporters
Section III: Platelet-Derived Factors
18 Dense Granule Factors
19 Protein Granule Factors
20 Lysosomal Storage
21 Thromboxane A2 and Other Eicosanoids
22 Platelet-Activating Factor: Biosynthesis, Biodegradation, Actions
23 Qualitative and Quantitative Assessment of Platelet Activating Factors
24 Biosynthetic Inhibitors and Receptor Antagonists to Platelet Activating Factor
Section IV: Clinical Aspects of Platelets and Their Factors
25 Platelets and the Vascular System: Atherosclerosis, Thrombosis, Myocardial Infarction
26 Platelets, Vessel Wall, and the Coagulation System
27 Platelet Flow Cytometry - Adhesive Proteins
28 Pathological Aspects of Platelet-Activating Factor (PAF)
29 Therapeutic Aspects of Platelet Pharmacology.