Defective Zn2+ homeostasis in mouse and human platelets with α- and δ-storage pool diseases

Summary(3H) noradrenaline was taken up by human platelets and partially converted into sulfoconjugated noradrenaline. This uptake was inhibited by drugs which have been previously shown to impair the uptake of 5-HT (ouabain, chlorimipramine) or the storage of 5-HT (tyramine, reserpine) by platelets. In addition, tyramine and reserpine stimulated the formation of sulfoconjugated noradrenaline. The efflux of noradrenaline from platelets was measured in parallel and was found to be directly related to the proportion of non metabolized to metabolized noradrenaline in the cells. Unlike tyramine, which induced a similar release of noradrenaline and 5-HT, reserpine was less effective at inducing noradrenaline release than 5-HT release. This study indicates a preferential localization of noradrenaline in the granular pool of human platelets with the existence of an extragranular sulfoconjugated pool which is increased when the granular storage of noradrenaline is impaired. Studies of noradrenaline fluxes and metabolism may be useful in the understanding of both acquired and inherited platelet storage pool defects.

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Depletion of Dense Granule Nucleotides during Storage of Human Platelets

Thrombosis and Haemostasis ◽

10.1055/s-0038-1645208 ◽

1990 ◽

Vol 63 (02) ◽

pp. 275-278 ◽

Cited By ~ 18

Author(s):

D de Korte ◽

C W N Gouwerok ◽

R Fijnheer ◽

R N I Pietersz ◽

D Roos

Keyword(s):

Specific Activity ◽

Adenine Nucleotide ◽

Human Platelets ◽

Dense Granule ◽

Serotonin Content ◽

Storage Pool ◽

Diadenosine Triphosphate ◽

Metabolic Pool ◽

And Storage ◽

Hydrolysis Of

SummaryThe energy metabolism of human platelets was studied during storage of platelet concentrates. The platelets were prepared from buffy coats in PVC/DEHP bags and stored for 7 days at room temperature at a concentration of 1.0 × 109/ml with horizontal agitation. The total amount of ATP and ADP decreased with 40% during this storage. This decrease correlated with the disc-tosphere transformation associated with the loss of platelet viability. During storage, the ability to incorporate 3H-adenosine into metabolic ATP and ADP (45 min at 37° C) decreased with 50%. Via measurement of the specific activity of actin-bound ADP and the amount of incorporated radioactivity into total ATP and ADP, we calculated the content of the metabolic and storage pools of ATP and ADP. The results indicate that the decrease in adenine nucleotide levels during storage was mainly caused by a depletion of ATP and ADP from the storage pool, whereas the metabolic pool remained nearly intact. After 7 days, the ATP : ADP ratio of the storage pool had decreased from 1.0 to 0.3, indicating hydrolysis of ATP.Diadenosine-triphosphate and diadenosine-tetraphosphate (present in the storage pool) decreased with only 30%, and the serotonin content remained nearly constant. Therefore, it is unlikely that the storage pool was completely secreted. Probably, the storage pool of nucleotides serves as an internal supply for maintaining the contents of the metabolic pool of ATP and ADP during storage of platelets.

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Inhibition of PF4 and ßTG Release from Platelets by Piracetam

10.1055/s-0039-1687600 ◽

1979 ◽

Author(s):

R.L. Henry ◽

R.M. Nalbandian ◽

G.E. Herman ◽

T. Ho

Keyword(s):

Platelet Aggregation ◽

Normal Individual ◽

Platelet Rich Plasma ◽

Human Platelets ◽

Complete Inhibition ◽

Clot Retraction ◽

Platelet Factor ◽

Storage Pool ◽

No Inhibition ◽

No Release

Platelet factor four (PF4) and beta-thromboglobulin (βTG) were released from human platelets alpha granules by ADP and epinephrine and measured by radioimmunoassay. Both release materials are antiheparins but PF4 is reported to be more potent. However, PF4 is released at about 1/4 the level of βTG in nanog rams/ml. Total release occurred with 5 ugm/rnl ADP in platelet-rich-plasma adjusted to 200,000 platelets/mm3 and with 1.25 × 10-5M epinephrine. No further release was found by freeze-thawing procedures. In one case, no release occurred although full aggregation proceeded normally with both mediators. Only minimal amounts were recorded after freeze-thawing indicating a storage pool deficiency of PF4 and βTG in an apparantly normal individual. Complete inhibition of PF4 and βTG release was obtained concurrently with elimination of the 2nd epinephrine wave by 6.4 × 10-4 M Piracetam. In contrast to aspirin, no inhibition of ADP, Collagen, or Ristocetin aggregation or release occurred with Piracetam. In previous work it was determined that Piracetam even at 6.4 × 10-3 M did not modify thrombin, prothrombin, or activated partial thromboplastin times. In addition, clot retraction was not modified in concentrations of Piracetam as high as 1.28 × 10-2 M known to eliminate the 2nd wave of platelet aggregation by epinephrine.

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Ultrastructural and Partial Biochemical Characterization of Platelets from Chediak-Higashi Cattle

10.1055/s-0039-1680402 ◽

1977 ◽

Author(s):

K. M. Meyers ◽

C. I. Seacord ◽

G. Hopkins ◽

H. Holmsen

Keyword(s):

Electron Micrographs ◽

Biochemical Characterization ◽

Platelet Rich Plasma ◽

Gel Filtration ◽

Human Platelets ◽

Additional Information ◽

Storage Pool ◽

Calcium And Magnesium ◽

Chediak Higashi Syndrome

To provide additional information on the platelet defect which is associated with the Chediak-Higashi syndrome (CHS), platelet rich plasma from normal and CHS cattle was incubated with 14C-adenine. Platelets were then isolated by gel filtration and treated with thrombin. Both the resting amount and extent of secretion of ATP, ADP, several acid hydrolasis, serotonin, calcium and magnesium was determined. Nucleotide profiles and electron micrographs of resting and thrombin treated platelets were also obtained. The markedly reduced secretion of nucleotides, serotonin, and metals demonstrate that CHS cattle have a storage pool defect. Furthermore, there appears to be significant differences in both the resting amount and extent of secretion of several of these measured substances between normal cattle and human platelets.

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Human platelets secrete chemotactic activity for eosinophils

Blood ◽

10.1182/blood.v81.1.49.49 ◽

1993 ◽

Vol 81 (1) ◽

pp. 49-55 ◽

Cited By ~ 40

Author(s):

JA Burgers ◽

RC Schweizer ◽

L Koenderman ◽

PL Bruijnzeel ◽

JW Akkerman

Keyword(s):

Receptor Antagonist ◽

Adenosine Triphosphate ◽

Platelet Activating Factor ◽

Thromboxane A2 ◽

Adenosine Diphosphate ◽

Human Platelets ◽

Chemotactic Activity ◽

Platelet Factor ◽

Storage Pool ◽

Web 2086

Abstract Thrombin-stimulated platelets liberate factors that induce chemotaxis of eosinophils and raise their cytosolic Ca2+ content ([Ca2+]i). The sources of this activity are the dense- and alpha-granules because inhibition of prostaglandin endoperoxide/thromboxane A2 formation and the platelet-activating factor receptor-antagonist WEB 2086 have no effect. Platelets from patients with Storage-Pool Deficiency show about 60% of the normal chemotactic activity with little effect on [Ca2+]i, whereas completely degranulated platelets fail to affect eosinophils. In concentrations secreted by the platelets, adenosine diphosphate (ADP), and platelet factor 4 have no effect, whereas adenosine triphosphate (ATP) induces a strong chemotactic response and increases [Ca2+]i. However, apart from ATP other modulating factors must be involved as platelet releasates induce more chemotaxis than ATP alone. Thus, platelets secrete factors that activate eosinophils and may contribute to inflammatory and allergic processes.

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Platelet Antiheparin Activity: Storage Site and Release Mechanism

Blood ◽

10.1182/blood.v44.2.157.157 ◽

1974 ◽

Vol 44 (2) ◽

pp. 157-168 ◽

Cited By ~ 39

Author(s):

Peter N. Walsh ◽

Giovanna Gagnatelli

Keyword(s):

Lysosomal Enzymes ◽

Time Course ◽

Adenosine Diphosphate ◽

Normal Subjects ◽

Human Platelets ◽

Release Mechanism ◽

Storage Site ◽

Dense Granules ◽

Storage Pool ◽

Platelet Storage

Abstract The platelet storage and release mechanisms for the heparin-neutralizing activity (HNA), adenosine diphosphate (ADP), serotonin, and lysosomal enzymes were investigated in normal human platelets and in platelets with defective storage or release of ADP and serotonin. The time course of release of HNA from normal washed platelets by thrombin and collagen was slower than that of serotonin. Lysosomal enzymes were not released by collagen from normal washed platelets, whereas under the same conditions HNA was released. In four of six patients with storage pool deficiency, the platelets contained normal amounts of HNA but definitely decreased amounts of ADP and serotonin, whereas in the remaining two patients the total contents of ADP, serotonin, and HNA were all definitely lower than normal. In four of six patients with storage pool deficiency, the amounts and per cents of total HNA released by collagen were normal, whereas the amounts and per cents of total ADP released were diminished compared with normal. Platelets from patients with the aspirinlike platelet release defect and from aspirin-treated normal subjects contained normal quantities of ADP, serotonin, and HNA, but HNA and ADP were not released in response to collagen. It is concluded that either HNA is stored in and released from dense granules by mechanisms different from those for ADP and serotonin, or that HNA is stored in and released from granules other than the dense granules, which contain ADP and serotonin and the α-granules, which contain lysosomal enzymes.

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Human platelets secrete chemotactic activity for eosinophils

Blood ◽

10.1182/blood.v81.1.49.bloodjournal81149 ◽

1993 ◽

Vol 81 (1) ◽

pp. 49-55

Author(s):

JA Burgers ◽

RC Schweizer ◽

L Koenderman ◽

PL Bruijnzeel ◽

JW Akkerman

Keyword(s):

Receptor Antagonist ◽

Adenosine Triphosphate ◽

Platelet Activating Factor ◽

Thromboxane A2 ◽

Adenosine Diphosphate ◽

Human Platelets ◽

Chemotactic Activity ◽

Platelet Factor ◽

Storage Pool ◽

Web 2086

Thrombin-stimulated platelets liberate factors that induce chemotaxis of eosinophils and raise their cytosolic Ca2+ content ([Ca2+]i). The sources of this activity are the dense- and alpha-granules because inhibition of prostaglandin endoperoxide/thromboxane A2 formation and the platelet-activating factor receptor-antagonist WEB 2086 have no effect. Platelets from patients with Storage-Pool Deficiency show about 60% of the normal chemotactic activity with little effect on [Ca2+]i, whereas completely degranulated platelets fail to affect eosinophils. In concentrations secreted by the platelets, adenosine diphosphate (ADP), and platelet factor 4 have no effect, whereas adenosine triphosphate (ATP) induces a strong chemotactic response and increases [Ca2+]i. However, apart from ATP other modulating factors must be involved as platelet releasates induce more chemotaxis than ATP alone. Thus, platelets secrete factors that activate eosinophils and may contribute to inflammatory and allergic processes.

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Defects of Platelet Function Recognized by X-Ray Imaging and Scanning Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100119806 ◽

1985 ◽

Vol 43 ◽

pp. 610-613

Author(s):

M.G. Baldini ◽

S. Morinaga ◽

D. Minasian ◽

R. Feder ◽

D. Sayre ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Cell Biology ◽

Imaging Technique ◽

Human Platelets ◽

X Rays ◽

X Ray ◽

X Ray Imaging ◽

Complex Phenomena ◽

Scanning Electron

Contact X-ray imaging is presently developing as an important imaging technique in cell biology. Our recent studies on human platelets have demonstrated that the cytoskeleton of these cells contains photondense structures which can preferentially be imaged by soft X-ray imaging. Our present research has dealt with platelet activation, i.e., the complex phenomena which precede platelet appregation and are associated with profound changes in platelet cytoskeleton. Human platelets suspended in plasma were used. Whole cell mounts were fixed and dehydrated, then exposed to a stationary source of soft X-rays as previously described. Developed replicas and respective grids were studied by scanning electron microscopy (SEM).

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Evaluation of platelet dense granules for determining storage pool deficiencies by HVEM image and quantitative analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100166312 ◽

1996 ◽

Vol 54 ◽

pp. 770-771

Author(s):

W.T. Gunning ◽

J.N. Turner ◽

K. Buttle ◽

E.P. Calomeni ◽

N.A. Lachant ◽

...

Keyword(s):

Quantitative Analysis ◽

Platelet Function ◽

Electron Microscopic ◽

Von Willebrand's Disease ◽

Dense Granules ◽

Storage Pool ◽

Prolonged Bleeding ◽

Microscopic Evaluation ◽

Storage Pools ◽

Electron Lucent

There are a variety of conditions which have been associated with prolonged bleeding times. If other etiologies including von Willebrand's disease have been ruled out, a platelet function disorder must be considered. The best, if not only, technique to make this diagnosis is the electron microscopic evaluation of whole air dried platelets. Bull first described the presence of dense granules in whole platelets in 1968 and the technique has been utilized extensively The electron dense or delta granules are easily distinguished from the larger more numerous alpha granules which are electron lucent. The significance of the dense granules is that they are known to be “storage pools” of serotonin, calcium, adenosine di- and triphosphate, and pyrophosphate. Prolonged bleeding times may be directly related to an insufficiency of these substances. The diagnosis of a storage pool deficiency is made when either the storage content of the dense granules is abnormal or their number is diminished. We observe normal platelets to have 4-6 dense granules, which agrees with the literature.

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In Vivo Monitoring of Human Platelets in a Humanised Rag2−/− γ-chain−/− Mouse Model

The Thoracic and Cardiovascular Surgeon ◽

10.1055/s-0035-1544477 ◽

2015 ◽

Vol 63 (S 01) ◽

Author(s):

C. Heim ◽

S. Müller ◽

B. Weigmann ◽

M. Ramsperger-Gleixner ◽

N. Koch ◽

...

Keyword(s):

Mouse Model ◽

Human Platelets ◽

In Vivo Monitoring

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