Inhibition of Rb+incorporation into HUVECs by E. coli LPS, ouabain or leptospiral GLP. The control group was incubated solely with KCl-free Hank’s solution containing non-radioactive Rb+. We compared the effects of ouabain (100, 250 and 500 nM), LPS 1 μg/mL and GLP (6 and 12 μg of GLP protein) in the experimental groups. Rb+ incorporation in cell cultures after 30 min of treatment was measured by ICP-OES. The results are expressed in μmol Rb+ incorporated per hour per 3 × 105 cells. Ouabain-sensitive inhibition of Na/K-ATPase is shown as a difference between Rb+ incorporation in the absence and in the presence of ouabain. Ouabain-insensitive Rb+ incorporation represents the amount of Rb+ entering cells through potassium channels and through passive diffusion. *P < 0.05 compared to the control group.