Different Functions of Phosphoinositide Turnover and Arachidonate Metabolism for Platelet Activation

1985 ◽  
pp. 387-392 ◽  
Author(s):  
Wolfgang Siess ◽  
Peter C. Weber ◽  
Eduardo G. Lapetina
Keyword(s):  
Platelet Activation ◽  
Phosphoinositide Turnover ◽  
Arachidonate Metabolism

Decreased Platelet Phosphoinositide Turnover and Enhanced Platelet Activation in IDDM

Diabetes ◽  
1989 ◽  
Vol 38 (9) ◽  
pp. 1097-1102 ◽  
Author(s):  
E. J. Bastyr ◽  
M. M. Kadrofske ◽  
R. C. Dershimer ◽  
A. I. Vinik
Keyword(s):  
Platelet Activation ◽  
Phosphoinositide Turnover

Decreased platelet phosphoinositide turnover and enhanced platelet activation in IDDM

Diabetes ◽  
1989 ◽  
Vol 38 (9) ◽  
pp. 1097-1102 ◽  
Author(s):  
E. J. Bastyr ◽  
M. M. Kadrofske ◽  
R. C. Dershimer ◽  
A. I. Vinik
Keyword(s):  
Platelet Activation ◽  
Phosphoinositide Turnover

The novel steroidal glycoside from the dried bulb of Allium Macrostemon Bunge inhibits platelet activation

2010 ◽  
Vol 34 (8) ◽  
pp. S33-S33
Author(s):  
Wenchao Ou ◽  
Haifeng Chen ◽  
Yun Zhong ◽  
Benrong Liu ◽  
Keji Chen
Keyword(s):  
Platelet Activation ◽  
The Novel ◽  
Steroidal Glycoside ◽  
Allium Macrostemon

In vivo lipid peroxidation and platelet activation in Helicobacter pylori infection

2001 ◽  
Vol 120 (5) ◽  
pp. A670-A670
Author(s):  
M NERI ◽  
G DAVI ◽  
D FESTI ◽  
F LATERZA ◽  
A FALCO ◽  
...  
Keyword(s):  
Lipid Peroxidation ◽  
Helicobacter Pylori ◽  
Platelet Activation ◽  
Helicobacter Pylori Infection

Characteristics of the Interaction between Thrombin Exosite1 and the Sequence 269-297 of Platelet Glycoprotein Ibα

1998 ◽  
Vol 80 (08) ◽  
pp. 310-315 ◽  
Author(s):  
Marie-Christine Bouton ◽  
Christophe Thurieau ◽  
Marie-Claude Guillin ◽  
Martine Jandrot-Perrus
Keyword(s):  
Platelet Activation ◽  
Electrostatic Interactions ◽  
Platelet Glycoprotein ◽  
Thrombin Receptor ◽  
Central Position ◽  
Amidolytic Activity ◽  
N Terminus ◽  
Hydrolysis Of ◽  
Chemical Cross Linking ◽  
Positively Charged

SummaryThe interaction between GPIb and thrombin promotes platelet activation elicited via the hydrolysis of the thrombin receptor and involves structures located on the segment 238-290 within the N-terminal domain of GPIbα and the positively charged exosite 1 on thrombin. We have investigated the ability of peptides derived from the 269-287 sequence of GPIbα to interact with thrombin. Three peptides were synthesized, including Ibα 269-287 and two scrambled peptides R1 and R2 which are comparable to Ibα 269-287 with regards to their content and distribution of anionic residues. However, R2 differs from both Ibα 269-287 and R1 by the shifting of one proline from a central position to the N-terminus. By chemical cross-linking, we observed the formation of a complex between 125I-Ibα 269-287 and α-thrombin that was inhibited by hirudin, the C-terminal peptide of hirudin, sodium pyrophosphate but not by heparin. The complex did not form when γ-thrombin was substituted for α-thrombin. Ibα 269-287 produced only slight changes in thrombin amidolytic activity and inhibited thrombin binding to fibrin. R1 and R2 also formed complexes with α-thrombin, modified slightly its catalytic activity and inhibited its binding to fibrin. Peptides Ibα 269-287 and R1 inhibited platelet aggregation and secretion induced by low thrombin concentrations whereas R2 was without effect. Our results indicate that Ibα 269-287 interacts with thrombin exosite 1 via mainly electrostatic interactions, which explains why the scrambled peptides also interact with exosite 1. Nevertheless, the lack of effect of R2 on thrombin-induced platelet activation suggests that proline 280 is important for thrombin interaction with GPIb.

Platelet Activation and Aggregation Induced by Recombinant von Willebrand Factors Reproducing Four Type 2B von Willebrand Disease Missense Mutations

1998 ◽  
Vol 79 (01) ◽  
pp. 211-216 ◽  
Author(s):  
Lysiane Hilbert ◽  
Claudine Mazurier ◽  
Christophe de Romeuf
Keyword(s):  
Platelet Aggregation ◽  
Platelet Activation ◽  
Von Willebrand Disease ◽  
Platelet Glycoprotein ◽  
Missense Mutations ◽  
Inhibit Platelet Aggregation ◽  
Wild Type ◽  
A1 Domain ◽  
Von Willebrand ◽  
Willebrand Factor

SummaryType 2B of von Willebrand disease (vWD) refers to qualitative variants with increased affinity of von Willebrand factor (vWF) for platelet glycoprotein Ib (GPIb). All the mutations responsible for type 2B vWD have been located in the A1 domain of vWF. In this study, various recombinant von Willebrand factors (rvWF) reproducing four type 2B vWD missense mutations were compared to wild-type rvWF (WT-rvWF) for their spontaneous binding to platelets and their capacity to induce platelet activation and aggregation. Our data show that the multimeric pattern of each mutated rvWF is similar to that of WT-rvWF but the extent of spontaneous binding and the capacity to induce platelet activation and aggregation are more important for the R543Q and V553M mutations than for the L697V and A698V mutations. Both the binding of mutated rvWFs to platelets and platelet aggregation induced by type 2B rvWFs are inhibited by monoclonal anti-GPIb and anti-vWF antibodies, inhibitors of vWF binding to platelets in the presence of ristocetin, as well as by aurin tricarboxylic acid. On the other hand, EDTA and a monoclonal antibody directed against GPIIb/IIIa only inhibit platelet aggregation. Furthermore, the incubation of type 2B rvWFs with platelets, under stirring conditions, results in the decrease in high molecular weight vWF multimers in solution, the extent of which appears correlated with that of plasma vWF from type 2B vWD patients harboring the corresponding missense mutation. This study supports that the binding of different mutated type 2B vWFs onto platelet GPIb induces various degrees of platelet activation and aggregation and thus suggests that the phenotypic heterogeneity of type 2B vWD may be related to the nature and/or location of the causative point mutation.

Effect of Ridogrel on Vascular Contractions Gaused by Vasoactive Substances Released during Platelet Activation

1990 ◽  
Vol 64 (01) ◽  
pp. 091-096 ◽  
Author(s):  
W J Janssens ◽  
F J S Cools ◽  
L A M Hoskens ◽  
J M Van Nueten
Keyword(s):  
Smooth Muscle ◽  
Blood Vessel ◽  
Platelet Activation ◽  
Prostaglandin F2α ◽  
Thromboxane A2 ◽  
Femoral Arteries ◽  
Vasoactive Substances ◽  
Caudal Artery ◽  
Isolated Rat ◽  
Rat Platelets

SummaryRidogrel (6.3 × 10−6 to 10−4 M) inhibited contractions of isolated rat caudal arteries and rabbit femoral arteries caused by U-46619. The slope of an Arunlakshana-Schild plot (pA2-value: 3.4 × 10−6 M) on the caudal artery was slightly higher than one (1.14). This effect was maximal within}D min of incubation of the blood vessel with the compound and easily reversible. Ridogrel antagonised contractions of isolated rabbit femoral arteries caused by prostaglandin Fzo2α in the same concentration range. Ridogrel also inhibited contractions induced by aggregating rat platelets on isolated rat caudal arteries (itt the presence of ketanserin 4 × 10−7 M) and on isolated rabbit pulmonary and femoral arteries (in the absence of ketanserin). Ridogrel had no effect on Ca2+-induced contractions in depolarised isolated rabbit femoral arteries, and at 10−4 M antagonised serotonin-induced contractions in this blood vessel. Its effect on serotonin-induced contractions was statistically significant but very small on isolated rat caudal arteries. These observations indicate that ridogrel is an antagonist of prostaglandin endoperoxide/thromboxane A2 and prostaglandin F2α raCeptors on vascular smooth muscle.

Sign in / Sign up

Export Citation Format

Share Document