Platelet aggregation, measurement inhibition

An in vitro or ex vivo measure of drug effect, for example, mean inhibitory concentration (MIC) of an antimicrobial against bacterial culture inhibition of ADP-induced platelet aggregation with a fibrinogen receptor antagonist. 

For prediction of likely in vivo activity, inhibition of ADP or U-46619 (a stable thromboxane A2 mimetic) induced platelet aggregation has been measured in citrated whole blood. The extent of aggregation is determined using a single platelet counter [33, 35, 38], Compounds may be less potent in the whole blood assay than in the partially purified platelet assays described above if the drug is significantly bound to plasma proteins. 

This compound may cause relaxation of skeletal muscle via general CNS depression. Aspirin inhibits prostaglandin synthesis, resulting in analgesia, antiinflammatory activity, and inhibition of platelet aggregation. It is indicated as an adjunct to rest, physical therapy, and other measures for the relief of discomfort associated with acute, painful, musculoskeletal conditions. 

The imidazole derivative, 4-(2-(lH-imidazol-l-yl)ethoxy) benzoic acid hydrochloride (UK-37,248), a thromboxane synthetase inhibitor, was given orally to healthy volunteers. Thromboxane levels in venous blood were measured, and it was found that the production of TXBj was inhibited in a dose-related manner [131]. After ingestion of 200 mg of the compound, arachidonic acid induced platelet aggregation was completely inhibited [132]. 

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