Background: Although several studies show that there is an increased risk of bleeding events during antidepressant treatment with selective serotonin reuptake inhibitors (SSRIs), few studies show direct effects in vitro of SSRIs on hemostasis. Methods: This study was undertaken to investigate the effects on platelet adhesion and plasma coagulation (APTT and PT) of two common SSRIs, citalopram a...

Bleeding time, platelet retention on glass beads, and ristocetin-induced platelet agglutination (RIPA) in platelet-rich plasma were simultaneously determined for 20 patients with chronic renal failure and previous hemorrhagic history. In seven patients chosen at random out of a group of 16 in whom the three tests were abnormal, RIPA of uremic-isolated platelets in presence of normal platelet-po...

THE FOLLOWING METHODS WERE USED TO MEASURE THE ADHESION TO VARIOUS SURFACES OF PLATELETS IN WHOLE BLOOD OR PLASMA: 1, two measurements gave an estimate in vivo of platelet adhesion to cut human capillaries; 2, platelets adhering to damaged cells in vitro were counted directly; 3, a highly reproducible method for estimating platelet adhesion to glass was devised; 4, the manner in which platelets...

A dose-response study of dietary fish oil supplementation on platelet adhesion was performed in three groups of five normal individuals each. Fish oil equivalent to 3, 6, or 9 g eicosapentaenoic acid (EPA)/day was administered for 3 weeks, and platelet adhesion was evaluated under high and low shear rate conditions in a laminar flow chamber before, during, and after termination of fish oil admi...

We have investigated the molecular basis of thrombus formation by measuring the extent of platelet deposition from flowing whole blood onto fibrin-coated glass coverslips under well-defined shear conditions in a rectangular perfusion chamber. Platelets readily and specifically adhered to fibrin-coated coverslips in 5 minute perfusion experiments done at either low (300 s-1) or high (1,300 s-1) ...

We have investigated the role of protein kinase C (PKC) in the initial events of alpha(2)beta(1)-integrin-mediated platelet adhesion to collagen under flow conditions. Although adhesion caused activation of PKC, as evidenced by pleckstrin phosphorylation, the PKC inhibitors GF 109203X and Gö 6976 had no effect on adhesion, even though they prevented pleckstrin phosphorylation. The initial kinet...

Platelet activation and aggregation by fibrillar collagens are based on substrate primary, secondary, tertiary, and quaternary structure. Although several peptides incorporating sequences from the triple-helical domains of types I and III collagen inhibit collagen-mediated platelet aggregation, none independently promote platelet activation and aggregation. It is believed that the absence of th...

Intravascular hemolysis occurs in patients on extracorporeal membrane oxygenation. High levels of free acellular adult hemoglobin (free HbA) are associated with clotting in this mechanical device that can result in thrombotic complications. Adsorption of fibrinogen onto the surface of biomaterial correlates with platelet adhesion, which is mediated by von Willebrand factor (VWF). Because free H...

The respective role of plasmatic and endothelial extracellular matrix (ECM)-associated von Willebrand factor (vWF) in platelet adhesion was investigated at a high shear rate using a parallel-plate perfusion chamber. Incubation of the endothelial ECM with a monoclonal antibody (MoAb) to vWF, which specifically blocks vWF binding to platelet GP Ib (MoAb 322), inhibited 45% of platelet adhesion. C...

Platelet adhesion in the annular perfusion system developed by Baumgartner was studied under pulsatile, oscillatory, or steady flow conditions. To investigate in what way pulsatile flow affects platelet adhesion, we developed a flow system that produces a sinusoidal laminar flow superimposed on a constant component in the annular perfusion chamber. Frequencies and amplitudes of this sinusoidal ...