Platelets: connecting clotting and lysis

Lysis of antibody-coated cells by platelets

Antibody-coated erythrocytes are lysed by murine C5- whole blood but not by plasma separated from such blood. The lytic activity has been shown to derive from platelets that attach to sensitized cells probably through membrane receptors for C3b. Whole blood or platelet-rich plasma (prp) obtained from mice that have been treated with purified cobra venom factor has little or no activity unless i...

Platelets inhibit the lysis of pulmonary microemboli.

Using tracings of (125)I-labeled fibrin(ogen) in rodents, we examined the hypothesis that platelets impede the lysis of pulmonary emboli. (125)I-Microemboli (ME, 3-10 micron diameter) lodged homogeneously throughout the lungs after intravenous injection in both rats and mice (60% of injected dose), caused no lethality, and underwent spontaneous dissolution (50 and 100% within 1 and 5 h, respect...

Some Effects on Platelets and Their Relationship to Clotting Tests

THE CLUMPING of platelets is probably the fundamental stage in the formation of thrombi. It was early demonstrated in experimental animals that administration of Dicnmarol (bishydroxyconmarin; Dicoumarol) in doses adequate to prevent thrombus formation was associated with delay or inhibition of platelet clumping.' ~ Although it may not be necessary to delay platelet clumping in order to prevent...

Effects of anticoagulants on clotting with low platelets

An action of thrombin on platelets in accelerating clotting.

By JANE F. DEsF0RGES, M.1). AND FREDERICK S. BIGELOw, M.1). W HILE THERE IS EVIDENCE for the thromboplastic activity of platelets plus a plasma factor during the itsit-iation of clottitig,’3 the part played by platelets once coagitlation has begitn is not svell (lehned. Quick has postulated that platelets are labilized by thrombits and that thereby a platelet factor is released ins increasing q...