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V Pribluda

Publications and source records attributed to V Pribluda.

6 recordsLinked to original sources
PubMed1982

Dynamics of membrane-cytoskeleton interactions in activated blood platelets.

The dynamics of actin polymerization, cytoskeleton formation, and interaction with membrane and cytoplasmic proteins as a result of platelet activation by temperature. ADP, or thrombin were studied. The polymerization of about 30% of platelet DNase I available actin to a nonavailable state is rapid and complete within 10 s after platelet activation with ADP and thrombin. This polymerization might be related to shape change rather than to aggregation or secretion. A similar value of actin polymerization is obtained when platelets are induced to change shape by cooling. This polymerization is partially reversible upon deactivation of the platelets by apyrase, hirudin, or rewarming. Cycles of temperatures-mediated activation and deactivation show a cyclic variation in the state of actin, with a tendency to refractivity to further changes after a couple of cycles. No correlation is observed between microtubule integrity and actin polmerization when studies are performed with platelets pretreated with colchicine. Analysis of the Triton residue composition shows that the cytoskeleton of resting platelets is composed mainly of actin and myosin in a 4.5:1 ratio. Activation with ADP and thrombin leads to the association and incorporation of several other protein (actin binding protein, 95 000 daltons, three to four proteins in the 35 000-dalton region, and two proteins in the 17 000-dalton region with the cytoskeleton). The incorporation of these proteins has a dynamic nature that depends on both the state of aggregation and the reversibility of the activation. Activation leads to a significant increase in the total cytoskeletal proteins, and although low temperature also induces such an increase, the cytoskeletal pattern of cooled platelets is not different from that of resting platelets. A complete reversibility in morphology and amount of protein was observed with temperature cycling. In light of these results, the dynamic nature of the state of actin in platelets is discussed.

Actins↗
PubMed1982

Photoaffinity labelling of the serotonin carrier protein in platelets and brain synaptosomes.

Azidoimipramine, a photoaffinity labelling reagent for the serotonin transport protein, was synthesized. This reagent, upon irradiation, binds covalently to brain synaptosomes preparation and to gel-filtered platelets. Two-dimensional SDS-polyacrylamide gel electrophoresis-isoelectric focusing and tritium fluorography analysis indicate that two synaptosomal proteins and four platelets proteins were labelled by [3H]azidoimipramine.

Affinity Labels↗
PubMed1981

The state of actin in activated human platelets.

The state of platelet actin was determined using a fluorescent method of DNAse I inhibition. Activation of human platelets resulted in mobilization of DNAse-available actin. When platelets were activated with ADP the change in the state of actin was gradual and preceded the secretion. When thrombin was used as an activator, a sharp and rapid decrease in the DNAse-available actin was observed which paralleled the secretion. Inhibition of ADP-induced aggregation (and secretion) by EDTA resulted in a decrease in the rate of change on actin. Inhibition of the thrombin-induced aggregation (but not secretion) by EDTA did not affect the change in the state of actin.

Actins↗