Figure 3.

Effect of plasmin on cell morphology. (a) Time 0: confluent lawn of resting A172 glial cells. (b) 30 minutes after addition of plasmin: cell processes have started retracting from basal substrata, and flaps of detached cells were observed, although cell-to-cell contacts were maintained. (c) 4 hours: A172 cells fully detached into a floating island. (d) 24 hours: shrivelled floating cell mass. (e) 24 hours: aprotinin (200 KIU/mL) preserved the confluent monolayer of A172 cells in the face of plasmin activation. (f) 24 hours: a PAR1 agonist peptide SFLLRN (25 μmoles/L) triggered analogous glial cell detachment as observed for plasmin in (d). Control peptide FSLLRN did not trigger any morphological changes (not shown). The magnification is indicated at the bottom right of each panel. Representative photomicrographs from n = 3–5 experiments are shown.