Thromb Haemost 1987; 58(03): 915-920
DOI: 10.1055/s-0038-1646015
Original Article
Schattauer GmbH Stuttgart

Human Gamma-Thrombin: Lack of Correlation Between a Platelet Functional Response and Glycoprotein V Hydrolysis

Martine Jandrot-Perrus
The Unité 150 INSERM and Unité Associée 334 CNRS, Hôpital Lariboisiére, Paris, and Laboratoire de Recherche sur I’Hémostase et la Thrombose, Faculté Xavier Bichat, Paris, France
,
Marie-Claude Guillin
The Unité 150 INSERM and Unité Associée 334 CNRS, Hôpital Lariboisiére, Paris, and Laboratoire de Recherche sur I’Hémostase et la Thrombose, Faculté Xavier Bichat, Paris, France
,
Alan T Nurden
The Unité 150 INSERM and Unité Associée 334 CNRS, Hôpital Lariboisiére, Paris, and Laboratoire de Recherche sur I’Hémostase et la Thrombose, Faculté Xavier Bichat, Paris, France
› Institutsangaben
Weitere Informationen

Publikationsverlauf

Received 23. April 1987

Accepted after revision 11. Juni 1987

Publikationsdatum:
28. Juni 2018 (online)

Preview

Summary

The ability of purified human gamma-thrombin to stimulate platelet function was related to its capacity to degrade GP V. Compared to alpha-thrombin, much greater amounts of gamma- thrombin were required to induce platelet aggregation; and this also applied to secretion from dense bodies, alpha-granules and lysosomal granules. Platelet stimulation by gamma-thrombin was additionally characterized by the presence of a lag-phase. Platelets with 3H-labelled surface glycoproteins showed the same functional response to both alpha- and gamma-thrombin as unlabelled platelets. But while threshold levels of alpha-thrombin induced little GP V hydrolysis confirming McGowan et al. (1), amounts of gamma-thrombin which induced substantial degradation (e. g. 8.3 nM degraded 36% of platelet GP V in 3 min) were unable to sustain either platelet aggregation or secretion. These results suggest that protein-binding regions remote from the catalytic site of alpha-thrombin are more important for platelet activation than GP V hydrolysis. They also provide further support to the argument that GP V hydrolysis may not be the essential trigger of platelet activation by thrombin.