Figure 5. Cholesterol-induced modulation of the P-gp ATPase activity in P-gp from DRM-containing and solubilized-membrane-containing fractions.

(A) P-gp was revealed by Western blot using the anti-P-gp C219 monoclonal antibody. Total proteins (10 μg) from F3, cholesterol-depleted F3 and cholesterol-repleted F3 fractions were deposited. Experimental conditions were identical for both cholesterol-depleted and cholesterol-saturated fractions. Cholesterol content in respectively F3 (B) and F7 (D) fractions after no treatment (ND), cholesterol depletion (D), cholesterol repletion (R) and saturation (S) of cholesterol. P-gp ATPase activity in respectively F3 (C) and F7 (E) fractions after no treatment, depletion, repletion and saturation of cholesterol. Experimental conditions are described in the Materials and methods section. Data represent means of triplicate experiments.