Low platelet arachidonic acid in young patients with brain infarction.

Fatty acid patterns of plasma and platelet lipids, platelet aggregation and thromboxane A2 (TxA2) production were studied in young patients (n = 12) with brain infarction and in healthy controls (n = 13). Platelet arachidonic acid content was significantly reduced in the stroke patients, but in vitro platelet aggregation was similar in the two groups. A low dose of acetosalicylic acid (ASA) (100 mg) suppressed thromboxane production and normalized the platelet arachidonic acid values. The low arachidonic acid in platelets is probably due to its increased consumption, indicating platelet activation in vivo.