The roles of alpha IIb beta 3-mediated outside-in signal transduction, thromboxane A2, and adenosine diphosphate in collagen-induced platelet aggregation.

Journal Article (Journal Article)

Collagen-induced activation of platelets in suspension leads to alpha(IIb)beta(3)-mediated outside-in signaling, granule release, thromboxane A2 (TxA2) production, and aggregation. Although much is known about collagen-induced platelet signaling, the roles of TxA2 production, adenosine diphosphate (ADP) and dense-granule secretion, and alpha(IIb)beta(3)-mediated outside-in signaling in this process are unclear. Here, we demonstrate that TxA2 and ADP are required for collagen-induced platelet activation in response to a low, but not a high, level of collagen and that alpha(IIb)beta(3)-mediated outside-in signaling is required, at least in part, for this TxA2 production and ADP secretion. A high level of collagen can activate platelets deficient in PLC gamma 2, G alpha q, or TxA2 receptors, as well as platelets treated with a protein kinase C inhibitor, Ro31-8220. Thus, activation of alpha(IIb)beta(3) in response to a high level of collagen does not require these signaling proteins. Furthermore, a high level of collagen can cause weak TxA2 and ADP-independent aggregation, but maximal aggregation induced by a high level of collagen requires TxA2 or secretion.

Full Text

Duke Authors

Cited Authors

  • Cho, MJ; Liu, J; Pestina, TI; Steward, SA; Thomas, DW; Coffman, TM; Wang, D; Jackson, CW; Gartner, TK

Published Date

  • April 1, 2003

Published In

Volume / Issue

  • 101 / 7

Start / End Page

  • 2646 - 2651

PubMed ID

  • 12446460

International Standard Serial Number (ISSN)

  • 0006-4971

Digital Object Identifier (DOI)

  • 10.1182/blood-2002-05-1363


  • eng

Conference Location

  • United States