Inhibition of Rb+incorporation in lung tissue by ouabain and OA. (A) Mice were divided into four groups. Lungs of mice from the control group were perfused with Rb free-Hank’s. Mice lungs from the second group were perfused with KCl free-Hank’s solution. The third group was perfused with KCl free-Hank’s plus ouabain and mice lungs from the 4th group were perfused with KCl free-Hank’s plus tris-oleate. Rb+ incorporation in lungs was measured after 15 min by ICP-OES in digested lung tissues. Results are expressed in μmol Rb+ incorporated per h per g of wet tissue ± SEM of 5 to 13 animals in each group. (B) Calculated percent of ouabain sensitive inhibition of Na/K-ATPase based on data from Figure 2A (the difference between Rb+ incorporation in absence and in presence of ouabain was considered as 100% enzyme activity). Ouabain insensitive Rb+ incorporation represents the amount of Rb+ into the tissue that enters through potassium channels and passive diffusion. The experiment was repeated twice. *P <0.002, compared to controls.