Influence of Apyrase on Stability of Suspensions of Washed Rabbit Platelets

Ardlie, N.G.; Perry, DW; Packham, Marian A.; Mustard, J. F.

doi:10.3181/00379727-136-35419

Cited by 141 publications

(63 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Another inhibitor of ADP-induced platelet reactions, apyrase, which hydrolyses ADP and blocks aggregation customarily attributed to platelet-derived ADP (55), also failed to inhibit platelet aggregation induced in citrated PRP by heparin. At concentrations of 210-350 ,ug/ml, apyrase strongly inhibited both the first and second phases of the platelet aggregation response to ADP, but there was no effect on heparin-induced platelet clumping.…”

Section: Resultsmentioning

confidence: 99%

Effect of Heparin and Heparin Fractions on Platelet Aggregation

Salzman¹,

Rosenberg²,

Smith³

et al. 1980

J. Clin. Invest.

620

202

View full text Add to dashboard Cite

A B S T R A C T Porcine intestinal mucosal heparin induced aggregation of platelets in citrated platelet-rich plasma and enhanced platelet aggregation and serotonin secretion induced by other agents. This action ofheparin was blocked by substances that elevate platelet cyclic AMP and by EDTA but not by inhibitors of platelet cyclooxygenase. The effect was not inhibited by apyrase or by N-amylthio-5'-AMP and therefore did not require the action of ADP, nor was there activation of platelet phospholipase. Platelet aggregation by heparin required a plasma cofactor different from the cofactor required for ristocetin.Fractionation of heparin yielded preparations that varied in molecular weight and, within a given molecular weight fraction, in affinity for antithrombin III.Fractions of high molecular weight (average 20,000) were more reactive with platelets than were fractions of low molecular weight (7,000). Anticoagulant activity did not parallel the platelet reactivity of heparin fractions. Among high molecular weight fractions, preparations of high or low antithrombin affinity were equally active in induction of platelet aggregation. In low molecular weight fractions, there was an inverse relationship between platelet reactivity and anticoagulant activity in normal platelet-rich plasma, but, in plateletrich plasma depleted of antithrombin, low molecular weight fractions of high and low antithrombin affinity reacted equally with platelets. These results suggest that formation of an antithrombin-heparin complex protected platelets from aggregation by heparin.Selection of heparin fractions of low molecular weight and high antithrombin affinity may improve anticoagulant therapy and development of thromboresistant heparin-coated artificial materials.

show abstract

Section: Resultsmentioning

confidence: 99%

Effect of Heparin and Heparin Fractions on Platelet Aggregation

Salzman¹,

Rosenberg²,

Smith³

et al. 1980

J. Clin. Invest.

620

202

View full text Add to dashboard Cite

show abstract

“…Suspensions of washed platelets were prepared at 23°C by the method of Ardlie et al (22,23). For biotin labeling, in the first washing step, platelets that had been recovered from platelet-rich plasma by centrifugation were suspended in calcium-free Tyrode's solution containing 0.52 mM EGTA and 0.35% albumin, pH 6.5 (one half volume of the original whole blood-ACD mixture).…”

Section: Preparation Of Platelet Suspensions For Injectionmentioning

confidence: 99%

Concurrent measurement of the survival of two populations of rabbit platelets labeled with either two PKH lipophilic dyes or two concentrations of biotin

et al. 2002

View full text Add to dashboard Cite

Background:To avoid radioisotopic labeling and permit comparison of the survival of two platelet populations concurrently in one animal, we compared simultaneous recoveries and survival times of homologous rabbit platelets labeled in vitro with the lipophilic dyes PKH26 (red fluorescing) and PKH67 (green fluorescing) and with two levels of biotin (low, 1 g/ml; high, 10 g/ml). Methods: Blood samples were drawn up to 96 h postinfusion and analyzed by flow cytometry. Biotin-labeled samples were incubated with phycoerythrin-streptavidin before analysis. Results: Recovery of PKH26-labeled platelets at 1 h was lower (37.5%) than that of PKH67-labeled platelets (47.3%; P Ͻ 0.001). Platelet survival times were 62.4 and 61.9 h. Recoveries at 1 h of platelets labeled with two levels of biotin were similar (86.6% and 84.6%) and greater

show abstract

“…Washed pig, rabbit, and human platelets were prepared according to previously published methods (8,9). After two washings, they were resuspended in Tyrode-albumin solution containing apyrase (10 ,ug/ml) which has been shown to stabilize platelet suspensions (10). The washing and suspending fluids used for the preparation of pig platelets were of a higher osmolarity than those used to prepare rabbit and human platelets, the difference amounting to an extra 50 mg KC1 and 90 mg NaCl/100 ml.…”

Section: Methodsmentioning

confidence: 99%

Platelet Interaction with Polymerizing Fibrin

Niewiarowski¹,

Rogoeczi²,

Steward³

et al. 1972

J. Clin. Invest.

156

View full text Add to dashboard Cite

A B S T R A C T Interaction of washed pig, rabbit, or human platelets with fibrinogen was studied during its transition to fibrin using photometric, isotopic, and electron microscopic techniques. Untreated fibrinogen and fully polymerized fibrin had no detectable effect on platelets. Fibrinogen, incubated with low concentrations of reptilase or thrombin, formed intermediate products which readily became associated with platelets and caused their aggregation. Neutralization of the thrombin did not prevent this interaction. In the absence of fibrinogen, reptilase did not affect platelets.The interaction of polymerizing fibrin with platelets was accompanied by small losses of platelet constituents (serotonin, adenine nucleotides, platelet factor 4, and lactic dehydrogenase). This loss did not appear to be the result of the platelet release reaction. Inhibitors of the release reaction or of adenosine diphosphate (ADP)-induced aggregation did not prevent the interaction of platelets with polymerizing fibrin. Apyrase or prostaglandin E1 (PGE1) reduced the extent of platelet aggregation by polymerizing fibrin, but the amount of protein associated with platelets was slightly increased.The interaction of polymerizing fibrin with platelets was completely inhibited by ethylenediaminetetraacetate (EDTA) or ethylene glycol bis (,-aminoethyl ether) N, N,N',N'-tetraacetic acid (EGTA).Fibers formed in solutions of polymerizing fibrin were larger in the presence than in the absence of washed platelets, suggesting that platelets affect fibrin polymerization. The adherence of platelets to polymerizing fibrin may be responsible for the establishment of links between platelets and fibrin in hemostatic plugs and thrombi.Dr. Stewart's present address is

show abstract

Influence of Apyrase on Stability of Suspensions of Washed Rabbit Platelets

Cited by 141 publications

References 2 publications

Effect of Heparin and Heparin Fractions on Platelet Aggregation

Effect of Heparin and Heparin Fractions on Platelet Aggregation

Concurrent measurement of the survival of two populations of rabbit platelets labeled with either two PKH lipophilic dyes or two concentrations of biotin

Platelet Interaction with Polymerizing Fibrin

Contact Info

Product

Resources

About