Thrombin-induced platelet aggregation inhibition

Williams, J. C., Forster, L. A., Tull, S. P., Wong, M., Bevan, R. J., and Ferns, G. A. (1997) Dietary vitamin E supplementation inhibits thrombin-induced platelet aggregation, but not monocyte adhesiveness, in patients with hypercholesterolaemia. Int J Exp Pathol 78,259-66. 

As shown in "Figs. (34) and (35) ", among the six saponins tested, only ginsenoside Rgi "Fig. (36)" inhibited adrenaline- and thrombin-induced platelet aggregation and 5-HT release dose-dependently. 

Xu and Feng investigated the effects of racemic butylphthalide and its enantionmers (S-, 32) and (/ -, 31) on platelet aggregation in rat PRP [300]. Both enantiomers and the racemic mixture (3-100 pM) dose-dependently inhibited platelet aggregation in rat PRP induced by ADP, collagen and AA, but did not affect thrombin-induced platelet aggregation. Furthermore, the S-enantiomer 32 and racemic mixture (10-100 pM) increased intracellular cAMP concentration in a dose-dependent manner. On the other... 

In addition, licochalcones A and B inhibited thrombin-induced platelet aggregation, dose-dependently "Fig. (40)". Moreover, licochalcones A and B inhibited calcium ionophore-induced production of LTs B4 and C4... 

In human platelets, the compound andrographolide inhibited platelet-activating-factor-induced aggregation in a dose-dependent manner (Amroyan et al. 1999). In mouse platelets, a standardized aqueous extract of andrographis, and the compounds andrographolide and 14-deoxy-ll,12-di-dehydroandrographolide inhibited thrombin-induced platelet aggregation in a dose-dependent manner (Thisoda et al. 2006). 

The compound ar-tumerone was shown to inhibit in vitro platelet aggregation induced by collagen or arachidonic acid but had no effect on platelet-activating factor or thrombin-induced platelet aggregation (Lee 2006). 

An aqueous extract of alfalfa inhibited ADP- and collagen-induced human platelet aggregation but had no effect on arachadonic acid- or thrombin-induced platelet aggregation. Alfalfa inhibited thromboxane B2 synthesis induced by ADP or collagen, and whole blood aggregation induced by collagen (Pierre et al. 2005). 

A partially purified fraction of Indian madder inhibited PAF-induced, but not thrombin-induced, platelet aggregation in rabbit platelets (Tripathi et al. 1993). 

In pig blood platelets, application of phenolic compounds, including fr ns-3,3, 5,5 -tetrahydroxy-4 -metho-xystilbene and yuccaols A and C, as a pretreatment slightly reduced platelet aggregation stimulated by ADP. With thrombin-induced platelet aggregation, the selected compounds exhibited significant inhibition of aggregation (Olas et al. 2002). 

Hemostatic and mild hypotensive activities have been reported (bradly). In an in vitro study, the aqueous extract of U. dioica dose dependently inhibited thrombin-induced platelet aggregation. The observed effect has been attributed to the flavonoid constituents of the extract. The hypotensive effects of U. dioica extracts (aqueous and methanohc, in vivo and in isolated organs) have also been reported by more than one group and the mechanism of action is suggested to be through vasodilation mediated by nitric oxide release, potassium channel opening, and negative inotropic action. ... 

SNAC is the most potent inhibitor of collagen-induced platelet aggregation in vitro compared to other S-nitrosothiols (SNAP, GSNO, CysNO and HomocysNo). Although it increased cGMP-levels in platelets [47], SNAC only partially inhibited thrombin-induced P-selectin expression on a platelet surface [79]. 

GEA-3175 is more stable than GEA-3162 in vitro but still retains its biological activity [95]. The release of NO and NO2 by GEA 3175 was increased 140-fold in the presence of human plasma, as analyzed by ozone chemiluminescence [94]. GEA 3175 inhibited agonist-induced platelet aggregation and induced a more than 4-fold increase in platelet cGMP without affecting cAMP levels [94]. Thrombin-stimulated rises in the cytosolic free Ca2+ concentration and secretion were dose-dependently inhibited by GEA 3175. GEA 3175 showed a reduced capacity to inhibit platelet aggregation of uremic platelets compared to controls [96]. 

Kawai H, Yamamoto T Hara H, et al. Inhibition of factor Xa-induced platelet aggregation by a selective thrombin inhibitor, argatroban. Thromb Res 1994 74 185-191. 

Antiplatelet Aggregation Activity. Alkaloids from Annonaceous plants were reported to inhibit platelet aggregation. According to our previous studies, more than twenty compounds were examined and most of the alkaloids were found inhibiting arachidonic acid (A.A) induced platelet aggregation [41]. Phenanthrene-alkaloids inhibited platelet aggregation initiated by four inducers (arachidonic acid, PAF, collagen, and thrombine)... 

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