Fig. 2.

Exogenous HSP70 neither induced injury or death in rat aortic endothelial cells (RAECs) nor had a cytoprotective role in cell injury in RAECs. Exogenous HSP70 was added with different doses and treatment times in the medium of primary cultured RAECs, while H₂O₂ and LPS were used as positive controls for cell injury and death, respectively. HSP70 did not induce any statistical change in cell LDH activity and survival rate in RAECs (a–d). The potential protective role of exogenous HSP70 was investigated in cell injury models. Different dose of recombinant HSP70 were added in the medium of RAECs simultaneously with the incubation of Ox-LDL or Hcy. The presence of HSP70 did not reverse the Ox-LDL or Hcy-induced increase in RAECs LDH activity (e–f). High dose of HSP70 was also administrated at times before the damaging compound. However, pretreatment with HSP70 for 8 or 24 h failed to decrease the level of LDH activity (g–h). Values represent mean ± SD, n = 3. *p < 0.05 vs. Ctrl