tPA protein level and activity as well as plasmin activity in rat brain.

<p>Western blot analysis of tPA protein levels in the rat brain 24 hr after intranasal administration of tPA (A). Bar graph (B) shows the tPA protein level. Of note, Sham+tPA rats received the same amount of intranasal tPA administration as TBI+tPA rats did. Representative zymographic assay (C) shows an increase in tPA activity in the Sham+tPA rats and TBI+tPA rats compared to TBI+Saline rats. h-r-tPA: human recombinant tPA (15 ng, Genentech). Bar graph (D) shows the tPA activity. Bar graph (E) shows amidolytic activity of plasmin assayed with D-Val-Leu-Lys-p-Nitroanilide Dihydrochloride (S-2251) as its specific substrate. Bar graph (F) shows tPA amidolytic activity with S-2251 as the substrate in the presence of added plasminogen compared to Sham. *<i>p</i><0.05 vs TBI+Saline. ^#<i>p</i><0.05 vs Sham+tPA. Data represent mean ± SD. n = 4 (rats/group, in graphs D, E, and F).