Fig. 4. Inhibitors of endocytic vesicular traffic reverse hepatoprotection induced by CGS21680. (A) Hepatocytes were incubated as explained in the legend to Fig. 3A, except that preconditioning was performed by incubating the cells for 15 minutes with the adenosine A2A-receptor agonist CGS21680 (1 µM). In some samples, 250 nM WM, 10 mM 3MA or 20 µM Cyt D were added during the treatment as indicated (see also text for details). (B) Hepatocyte viability was evaluated after incubating for 60 minutes under control or hypoxic conditions in non-preconditioned and preconditioned hepatocytes. Data (means±s.d. of four experiments) demonstrate that WM, 3MA and Cyt D nullified the cytoprotective effect of CGS21680. (*P<0.001, statistical significance vs hypoxia and vs CGS incubated under hypoxia in the presence of inhibitors.)