Neuroprotection by early and delayed treatment of acute stroke with high dose aspirin.

Acetylsalicylic acid (ASA; Aspirin) has a neuroprotective potential by its anti-excitotoxic and anti-inflammatory effects. A temporary middle cerebral artery occlusion (tMCAO) model was used in 80 Wistar rats to evaluate whether a high dose of Aspirin (40 mg/kg) applied with different initiation time points after stroke onset (30 min, 3 h, 6 h, 12 h, 20 rats for each time group) and followed by repeated administration (1, 2 and 3 days) is neuroprotective. Neurological score and brain infarct volume were analyzed and indicated that postischemic therapy initiation at 30 min and as late as 6 h led to better neurological recovery (6 h, p=0.0046) and significant smaller infarct size (6 h, 57+/-9 mm(3), n=10, p=0.0043) compared to the saline control group (110+/-13 mm(3), n=10). Thus, there may be a relatively wide time window for acute stroke therapy with high dose Aspirin.