Platelet/Thrombocyte
Acetylsalicylic acid (ASA) irreversibly inhibits the cyclooxygenase and thus prevents the conversion of arachidonic acid to thromboxane A2 (TxA2). This effect translates into the inhibition of thromboxane A2-dependent platelet aggregation and vasoconstriction.
The Formulation of Aggrenox® - The Antiplatelet Activity of ASA
ASA prevents platelet aggregation by irreversibly acetylating platelet cyclooxygenase, thereby interrupting the arachidonic cascade and preventing synthesis of thromboxane A2, a potent thrombogenic. In humans, platelet cyclooxygenase is completely inhibited with ASA doses as low as 30 mg daily.
References
Boehringer Ingelheim Data on File 2002.
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PubMed Abstract
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PubMed Abstract
The arachidonic cascade also produces prostacyclin, a potent antithrombotic. ASA inhibits prostacyclin synthesis by inhibiting vessel-wall cyclooxygenase, especially at high doses.
This observation led to the idea of using low-dose ASA for its inhibitory effects on thromboxane while minimising its inhibitory effects on prostacyclin.
Low-dose ASA also minimises adverse effects on the gastrointestinal tract.
References
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PubMed Abstract
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PubMed Abstract
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PubMed Abstract
