Influence of hypotension (moderate, severe) and isoproterenol (10−8,10−6 M) on pial artery diameter in pigs before (sham control), and after photothrombotic injury (PTI), or treated at 4h post injury with wt-tPA (1 mg/kg iv), tPA + MK801 (10−5 M), tPA-A296-299 (1 mg/kg iv), tPA-A296-299 + IgG (10 μg/ml), tPA-A296-299+ anti-LRP Ab (10 μg/ml), tPA-A296-299 + RAP (10−7 M), or tPA-A296-299 + SB203580 (1mg/kg iv), n=5. *p<0.05 versus corresponding sham control value +p<0.05 versus corresponding untreated PTI value #p<0.05 versus tPA-A296-299 alone.