<p>OBJECTIVETo determine the change of P-selectin in avulsion-injured vessels.p><p>METHODSDifferent stretch forces of 60, 70, 80 and 90 g were applied to a vascular injury model. The expression changes of P-selectin were evaluated by RT-PCR.p><p>RESULTSThe expression of P-selection mRNA in the injured vessels increased with the stretch force.p><p>CONCLUSIONThe result associated with our previous study indicated that P-selectin may be involved in thrombosis.p>
Animals ; Endothelium, Vascular ; P-Selectin ; metabolism ; RNA, Messenger ; metabolism ; Vascular System Injuries ; genetics ; metabolism

Human platelets have distinct characters when preserved by different methods. A efficient flow cytometric assay for different preserved platelets expression of CD62p and phosphatidylserine(PS) is in dire need. Efficient flow cytometric assay for CD62p and PS expressed by preserved platelets was established and the major conditions were optimized. The platelets need not to be washed to wipe off plasma and can be labelled diredtly during the sample preparation. It is efficient for flow cytometric analysis when fresh platelet riched plasma (FPRP) was set as negative control, thrombin actived FPRP, and liquid nitrogen treated FPRP were set as positive control respectively. Gly-Pro-Arg-Pro acetate salt (GPRP) was applied to prevent platelets aggregation and fibrin formation, stabilize platelets and minimize the artificial platelets activation. This is also the key to conquer difficulty of flow cytometric quantitive analysis when platelet, Ca(2+) and plasma coexist. This flow cytometric method is specially suitable for the multi-parameter assay including PS expression for cryopreserved platelets. Minimal sample manipulation, no fixation, and GPRP application resulted in minor artifacts and good sample stability. Results suggested, this flow cytometric assay for preserved platelets is simple and efficient. In addition, the author prepared four different methods treated platelets that can be easily distinguished through this flow cytometric assay. It not only makes sure the practicability of this flow cytometric assay, but also suggests the value of the treated platelets applied in preserved platelets flow cytometric ass
Blood Platelets ; metabolism ; Flow Cytometry ; methods ; Humans ; P-Selectin ; biosynthesis ; Phosphatidylserines ; analysis ; Reproducibility of Results ; Tissue Preservation

In order to explore the factors that affect CD62p expression in platelet during the whole course of cryopreservated platelets preparation, CD62p expression of platelet was evaluated by flow cytometry assay. The whole course of cryopreservated platelets preparation in order included whole blood collection, centrifugation for fresh platelet-rich plasma preparation, addition of dimethyl sulfoxide, and freeze in -80 degrees C refrigerator and thaw in 38 degrees C water bath. Result showed that the CD62p expressed slowly from whole blood collection to addition of dimethyl sulfoxide, but expressed abruptly after freeze and thaw and it occupied 82 per cent of the whole expression. It was concluded that the whole blood collection, centrifugation for fresh platelet enriched plasma preparation and addition of dimethyl sulfoxide were optimized in the whole course, but the damage to platelets in the whole course of cryopreservation could not be avoided. It suggests that improved techniques are needed to reduce the damage to cryopreservated platelets.
Blood Platelets ; metabolism ; Blood Preservation ; methods ; standards ; Cryopreservation ; methods ; standards ; Flow Cytometry ; Humans ; P-Selectin ; biosynthesis

P-selectin, one of the membrane proteins, expresses on platelet and endothelia and interacts with P-selectin glycoprotein ligand-1 (PSGL-1) on leukocyte membrane. This interaction mediates leukocytes rolling on endothelial membrane and then induces leukocyte recruitment to the site of infection or tissue injury. In the present study, we constructed the recombinant wild type human P-selectin, its calcium-binding sites mutants and recombinant PSGL-1-globulin (PSGL-1-Rg). They expressed in Sf9 cells by using the baculovirus expression system and were purified by TalonTM metal or Protein A affinity chromatography. The results showed that the recombinant PSGL-1-Rg interacted with recombinant wild type P-selectin and two P-selectin mutants with 2 calcium-binding sites mutation respectively, but could not bind to the P-selectin mutant with all 4 calcium-binding sites mutation. Therefore, we verified the importance of P-selectin calcium-binding sites for its interaction with PSGL-1.
Binding Sites ; Calcium ; metabolism ; Humans ; Leukocytes ; metabolism ; Membrane Glycoproteins ; metabolism ; Mutation ; P-Selectin ; metabolism ; Recombinant Proteins ; metabolism

P-selectin engagement of P-selectin glycoprotein ligand-1 (PSGL-1) causes circulating leukocytes to roll on and adhere to the vascular surface, and mediates intracellular calcium flux, a key but unclear event for subsequent arresting firmly at and migrating into the infection or injured tissue. Using a parallel plate flow chamber technique and intracellular calcium ion detector (Fluo-4 AM), the intracellular calcium flux of firmly adhered neutrophils on immobilized P-selectin in the absence of chemokines at various wall shear stresses was investigated here in real time by fluorescence microscopy. The results demonstrated that P-selectin engagement of PSGL-1 induced the intracellular calcium flux of firmly adhered neutrophils in flow, increasing P-selectin concentration enhanced cellular calcium signaling, and, force triggered, enhanced and quickened the cytoplasmic calcium bursting of neutrophils on immobilized P-selectin. This P-selectin-induced calcium signaling should come from intracellular calcium release rather than extracellular calcium influx, and be along the mechano-chemical signal pathway involving the cytoskeleton, moesin and Spleen tyrosine kinase (Syk). These results provide a novel insight into the mechano-chemical regulation mechanism for P-selectin-induced calcium signaling of neutrophils in flow.
Calcium Signaling ; Female ; Humans ; Male ; Membrane Glycoproteins ; metabolism ; Neutrophils ; metabolism ; P-Selectin ; metabolism ; Stress, Mechanical ; Syk Kinase ; metabolism

Animals ; Hindlimb ; blood supply ; Ischemic Preconditioning ; Lung ; metabolism ; Male ; P-Selectin ; metabolism ; Rats ; Rats, Wistar ; Reperfusion Injury ; metabolism

<p>OBJECTIVETo observe the expression of P-selectin in the penile vascular epithelial cells and the morphological changes in the ultrastructure of the penile cavernous tissues of smoking rats, and to explore the pathogenesis of smoking-induced erectile dysfunction.p><p>METHODSFifty healthy Wistar rats were randomly divided into a normal control, a long-term heavy smoking group, a long-term light smoking, a short-term heavy smoking and a smoking cessation group. Their erectile function was tested by subcutaneous injection of apomorphine (APO), the P-selectin expression in the penile vascular epithelial cells detected by ELISA and the morphological changes in the ultrastructure of the penile cavernous tissues observed under the transmission electron microscope (TEM).p><p>RESULTSThe levels of P-selectin were 10.78 +/- 1.71 ng/L, 62.62 +/- 5.95 ng/L, 40.06 +/- 3.97 ng/L, 41.37 +/- 4.06 ng/L and 22.80 +/- 3.15 ng/L respectively in the normal control, long-term heavy smoking, long-term light smoking, short-term heavy smoking and smoking cessation groups, with significant differences between the control group and the other four (P < 0.05). Electron microscopy showed abnormal arrangement of endothelia, penile cavernous sinuses and smooth muscle cells, disrupted continuity of endothelia, damaged ultrastructure of endothelial and smooth muscle cells in the penile cavernous tissue, and obvious proliferation and fibrosis of interstitial tissues in the smoking rats.p><p>CONCLUSIONSmoking increases the P-selectin expression in the penile vascular epithelial cells and damages the ultrastructure of the penile cavernous tissue, which may be the main contributors to smoking-induced erectile dysfunction.p>
Animals ; Epithelium ; metabolism ; Male ; P-Selectin ; biosynthesis ; Penile Erection ; Penis ; blood supply ; metabolism ; ultrastructure ; Rats ; Rats, Wistar ; Smoking ; adverse effects

Cell Line ; Human Umbilical Vein Endothelial Cells ; drug effects ; metabolism ; Humans ; Interleukin-1 ; administration & dosage ; pharmacology ; P-Selectin ; metabolism

<p>OBJECTIVETo explore the relationship between expression thange of P-selectin after brain injury and secondary brain damage.p><p>METHODSSixty SD rats were randomized into 3 equal groups, namely the control group, mild injury group and severe injury group and animal models of brain injury were established in SD rats according to the method of Feeney. P-selectin expression in the brain tissues were determined at 6 h and l, 3, and 7 days following brain injury (n=5 for each time point). Imaging analysis was performed using computerized imaging technique.p><p>RESULTSP-selectin expression and neutrophil infiltration in the brain tissues increased significantly 6 h after brain injury (P<0.05), reaching the peak level at postoperative 24 h and then gradually decreased.p><p>CONCLUSIONP-selectin expression and neutrophil infiltration increase significantly following brain injury, and the time course and distribution of P-selectin expression are consistent with the secondary damage of the brain, strongly suggesting the involvement of P-selectin upregulation in the secondary insult after brain injury.p>
Animals ; Brain Chemistry ; Brain Injuries ; etiology ; metabolism ; pathology ; Female ; Immunohistochemistry ; P-Selectin ; biosynthesis ; Random Allocation ; Rats ; Rats, Sprague-Dawley

The objective of this study was to explore the changes of aggregation function of apheresis platelets and soluble P-selectin (sP-selectin) during storage. 20 samples of apheresis platelets were collected, and the aggregation function were examined by function test and the level of sP-selectin every day in storage of 5 days. The results showed that the aggregation function of platelets declined obviously during storage, there were significant differences between the first-day group and any of the other groups (p < 0.01). The max platelet aggregation rate was < or = 3% in the fourth-day group; sP-selectin level in plasma increased with prolong of storage time; there were significant differences between the first-day group and any of the other groups (p < 0.05). In conclusion, platelets were activated continuously during storage, while its aggregation function declines significantly. The ability of platelet aggregation to response to ADP loses almost completely since the fourth day during platelet storage. It should be paid more attention to the damage of apheresis collected platelets during storage.
Adult ; Blood Platelets ; metabolism ; physiology ; Humans ; Male ; P-Selectin ; blood ; Platelet Aggregation ; Platelet Count ; Plateletpheresis ; methods ; Specimen Handling