Effect of GLP-2 on activity and expression of hepatic, intestinal, and renal Mrp2. A, excretion rate of DNP-SG, prototypical substrate for Mrp2, and its derivative DNP-CG was assessed in bile, intestinal perfusate, and urine at 10-, 15-, and 30-min collection periods, respectively, for 90 min. Insets depict cumulative excretion of DNP-SG by 90 min. The data represent means ± S.D. of four rats per group. *, significantly different from control (C), P < 0.05. B, Mrp2 protein was detected by Western blot of hepatic, intestinal, and renal membranes from GLP-2 and control rats. Protein (5 and 30 μg) from liver crude plasma membranes and brush-border membranes from proximal jejunum and renal cortex, respectively, were loaded in the gels. Uniformity of loading and transfer from gel to PVDF membrane was controlled with Ponceau S. Mrp2 expression was normalized relative to β-actin expression; data on densitometric analysis are presented as percentages relative to control, considered as 100%, and were expressed as means ± S.D. of six rats per group. *, significantly different from control (C), P < 0.05.