Release of β-Lysin from Platelets by Thrombin and by a Factor Produced in Heparinized Blood

Open Access
Publisher Website
Google Scholar
Abstract
Removal of calcium by either citrate, oxalate, or ethylenediaminetetraacetate inhibited coagulation of blood at an early stage and prevented the release of β-lysin from platelets. In contrast, heparin caused platelet agglutination and stimulated β-lysin release in vitro and in vivo. This release was calcium dependent and may have been due to a calcium-dependent reaction in the blood coagulation sequence. Thrombin which by-passed the early calcium-dependent stages of coagulation directly stimulated the release of β-lysin from platelets. However, thrombin alone or in combination with other plasma factors was not as effective in releasing β-lysin as the regular coagulation process. Thrombin's platelet degranulating activity correlated with its β-lysin releasing activity. In contrast to thrombin, staphylococcal coagulase, which also by-passed the calcium-dependent stages of coagulation, coagulated citrated blood without releasing β-lysin. The release of β-lysin has been observed previously in the absence of blood coagulation, but this is the first observation of coagulation without β-lysin release. It is clear that β-lysin is released from platelets during coagulation by the direct action of thrombin and that it may be released in an earlier calcium-dependent reaction.

This publication has 0 references indexed in Scilit: