Inhibition of myosin ATPase blocks contractility and up-regulates blebbing.

Confluent endothelial cells were preincubated with either vehicle control (DMSO; B) or BDM (5 mM, 30 minutes; A,C-H). In panels E and F, cells were preincubated with SB203580 (10 μM, 30 minutes) together with BDM and in panels G and H with cytochalasin D (10 nM, 30 minutes) together with BDM. Then cells were exposed to CA-4-P (1 μM, 60 minutes; B,C,D,F,H) and fixed and stained with Texas Red phalloidin. Panel D represents a higher magnification of cells in panel C. Bar for panels A-C and panels E-F = 42 μm; bar for panel D = 25 μm.