Platelet Aggregation A

Lau WC. Atorvastatin reduces the ability of clopidogrel to inhibit platelet aggregation a new drug-drug interaction. Circulation 2003 107 32-7. 

Inhibition of platelet aggregation, a crucial factor in ischemic disorders... 

Von Willebrand factor plays a key role in thrombogenesis. Lack of this factor is the cause of thrombasthenia, the inability to staunch bleeding by platelet aggregation. A relative deficiency of von Willebrand factor can be transiently relieved by injection of the vasopressin analogue desmopressin because this substance makes factor available from stored supplies. 

Few seconds later more platelets are deposited on the collagen fibrils and the platelets are now also sticking to each other (platelet aggregation). A growing platelet plug is formed in the lesion of the vessel wall as more platelets aggregate. At a certain stage in diis process, red blood cells are no... 

Vaughan DE, Kirshenbaum JM, Loscalzo J. Streptokinase-induced, antibody-mediated platelet aggregation a potential cause of clot propagation in vivo. J Am CoU Cardiol 1988 ll(6) 1343-8. 

Morris J, Bure V, Mori T, et al. Effects of garlic extract on platelet aggregation a randomized placebo-controlled double-blind study. Clin Exper Pharm Phys 1995 22 414 U7. 

Two types of thrombocytopenia associated with heparin use have been described. " As many as of 25% of patients receiving heparin therapy develop a benign, mild reduction in platelet counts referred to as non-immune-mediated heparin-associated thrombocytopenia (HAT) or previously called HIT type 1. HAT produces a transient fall in platelet count that occurs early, typically between days 2 and 4, during the course of therapy. The degree of thrombocytopenia is usually mild, with platelet counts rarely going below 100,000/mm . It is not necessary to discontinue heparin therapy in these patients because platelet counts generally rebound to baseline values despite continued use. The exact mechanism of HAT is unknown, but it may be the result of platelet aggregation, a dilutional effect, or diminished platelet... 

VITAMIN E AND PLATELET AGGREGATION a-Tocopherol, a natural antioxidant, inhibits platelet aggregation and release. The effect of vitamin E is dne to a redaction in platelet cyclooxygenase activity and inhibition of lipid peroxide formation. It is believed that snpplementing the diet with vitamin E could play a role in the treatment of thromboembolic disease, especially if it is given in conjnnc-tion with an inhibitor of platelet aggregation. 

The mechanism of action of the immunological and anti-inflammatory effects of antimalarials include inhibition of phospholipase A, inhibition of platelet aggregation, a range of lysosomal effects (e.g., an increase in pH, membrane stabilization, and inhibition of release and activity of lysosomal enzymes), inhibition of phagocytosis, an increase in intracellular pH in cytoplasmic vacuoles leading to decreased stimulation of autoimmune CD4 T cells, decreased cytokine release from lymphocytes and stimulated monocytes, inhibition of immune complex formation, and antioxidant activity. In patients with porphyria cutanea tarda, chloroquine and hydroxychloroquine bind to porphyrins and/or iron to facilitate their hepatic clearance. The ability to bind to melanin and other pigments may contribute to the retinal toxicity seen occasionally when anti-malarial agents are used. 

Thrombin is a protease and a potent physiological activah of platelet aggregation, a process of key significance to bol hemostasis and thrombosis. Thrombin acts on proteasi... 

Lau WC, Waskell LA, Watkins PB, Neer CJ, Horowitz K, Hc p AS, Tait AR, Carville DGM, Guyer KE, Bates ER. Atorvastatin reduces die ability of clopidogrel to inhibit platelet aggregation. A new drug-drug interaction. Circulation ( 3) 107,32-7. 

Young, H.Y., J.C. Liao, Y.S. Chang, et al. 2006. Synergistic effect of ginger and nifedipine on human platelet aggregation A study in hypertensive patients and normal volimteers. Am. J. Chin. Med. 34(4) 545-551. 

The amount of co-3 fatty acids required is still under discussion. At first, due to the activity of desaturases, the biological effects of a-linolenic acid and EPA in the diet were thought to be very different. In view of the platelet aggregation, a tenfold amount of a-linolenic acid is necessary to yield the effect of EPA [1] (Fig. 2). From this experience - in contrast to o)-6 fatty acids - we might need two different requirement figures for (o-3 fatty acids, a greater one for a-linolenic add and a lower for EPA. That demands the use of a o)-3 fatty acid equivalent doses when formulating recommendations. 

Wojcikowski K, Myers S, Brooks L (2007) Effects of garlic oil rai platelet aggregation a double-blind placebo-controlled crossover study. Platelets 18(l) 29-34. doi 10.1080/ 09537100600800636... 

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