A plasminogen proactivator-activator system in human blood effective in absence of hageman factor

SummaryIn serum from patients with DIC at least 3 different FR-antigenic components could be found. It was difficult to demonstrate these components in the corresponding plasma samples. It is possible that a portion of these antigens formed as a result of in vitro clotting despite the presence of proteolytic inhibitors. These results suggest that the interpretation of “increased split products in serum” may be more complex than current concepts indicate.

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On the Mechanism by which Cell Contact Induces the Release Reaction of Blood Platelets; the Effect of Cationic Polymers

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649347 ◽

1972 ◽

Vol 27 (01) ◽

pp. 121-133 ◽

Cited By ~ 14

Author(s):

P Massini ◽

E. F Lüscher

Keyword(s):

Human Blood ◽

Calcium Ions ◽

Blood Platelets ◽

Cell Contact ◽

Second Phase ◽

Cationic Polymers ◽

Release Reaction ◽

Per Se ◽

Human Blood Platelets

SummaryHuman blood platelets are aggregated by the basic polymers polylysine and DEAE- dextran. Under certain conditions a second phase of aggregation, concomitant with the release reaction, is elicited. The presence of ADP, calcium ions and a plasmatic cofactor within the primary aggregates are necessary for the induction of the release reaction. These experiments demonstrate that cell contact per se does not lead to a release reaction ; in order to become effective it must take place in the presence of ADP.

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Effect of Aspirin on the Thrombelastogram of Human Blood

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649127 ◽

1973 ◽

Vol 30 (03) ◽

pp. 494-498 ◽

Cited By ~ 1

Author(s):

G de Gaetano ◽

J Vermylen

Keyword(s):

Oral Dose ◽

Single Oral Dose ◽

Platelet Function ◽

Human Blood ◽

Platelet Rich Plasma ◽

Plasma Samples ◽

Release Reaction ◽

Platelet Release

SummaryThrombelastograms of both native blood and re-calcified platelet-rich plasma samples taken from subjects given a single oral dose of aspirin (1 gram) were not significantly different from the pretreatment recordings. Aspirin also did not modify the thrombelastogram when preincubated in vitro with platelet-rich plasma at concentrations inhibiting the platelet “release reaction” by collagen. Thrombelastography therefore cannot evaluate the effect of aspirin on platelet function.

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The Effect of Dipyridamole and RA 233 on Human Platelet Function in Vitro

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648112 ◽

1973 ◽

Vol 29 (03) ◽

pp. 694-700 ◽

Cited By ~ 4

Author(s):

Paul L. Rifkin ◽

Marjorie B. Zucker

Keyword(s):

Mechanism Of Action ◽

Human Blood ◽

Glass Bead ◽

Heart Valves ◽

Human Platelet ◽

Drug Effects ◽

Simple Relation ◽

Prosthetic Heart Valves ◽

Induced Aggregation

SummaryDipyridamole (Persantin) is reported to prolong platelet survival and inhibit embolism in patients with prosthetic heart valves, but its mechanism of action is unknown. Fifty jxM dipyridamole failed to reduce the high percentage of platelets retained when heparinized human blood was passed through a glass bead column, but prolonged the inhibition of retention caused by disturbing blood in vitro. Possibly the prostheses act like disturbance. Although RA 233 was as effective as dipyridamole in inhibiting the return of retention, it was less effective in preventing the uptake of adenosine into erythrocytes, and more active in inhibiting ADP-induced aggregation and release. Thus there is no simple relation between these drug effects.

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