TY - JOUR T1 - Close Relationship between the Platelet Activation Marker CD62 and the Granular Release of Platelet-Derived Growth Factor JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 952 LP - 957 DO - 10.1124/jpet.300.3.952 VL - 300 IS - 3 AU - Jochen Graff AU - Ute Klinkhardt AU - Valérie B. Schini-Kerth AU - Sebastian Harder AU - Nicole Franz AU - Steffen Bassus AU - Carl M. Kirchmaier Y1 - 2002/03/01 UR - http://jpet.aspetjournals.org/content/300/3/952.abstract N2 - The expression of CD62 on the surface of platelets is considered to be an indicator of platelet degranulation and secretion. We characterized the relationship between CD62 expression and platelet-derived growth factor (PDGF)AB and PDGFBB secretion in response to thrombin-receptor activating peptide (TRAP). The principal findings were 1) expression of CD62 as a constituent of platelet α-granule membrane and secretion of PDGF, an important ingredient of α-granules, can be stimulated by TRAP-induced activation in a dose-dependent fashion; 2) the activation marker and secretion product are closely correlated with each other; and 3) changes in the CD62 expression induced by a drug, namely clopidogrel, or by a disease, namely diabetes, are paralleled by changes in PDGF secretion. Although CD62 is perceived as an activation marker of platelets indicating enhanced aggregability and secretion of α-granular content, the proof that the CD62 status and its modifications reflect directly the actual secretion of the most important platelet mitogen, PDGF, has so far not been given. This ex vivo-in vitro study shows that at least for the activation pathway provided by the PAR-1 receptor for which TRAP is the selective agonist, CD62 expression on platelets could be a surrogate for their secretory activity. The American Society for Pharmacology and Experimental Therapeutics ER -