Fig. 5

a A schematic diagram of the three concurrent processes of renal clearance: glomerular filtration, tubular secretion and tubular reabsorption, and the major renal tubular drug transporters involved in the uptake and secretion of s-GOs and l-GOs. b The mRNA expression levels b–h of renal tubular drug transporters, including organic anion transporter 1 (Oat1/Slc22a6) and 2 (Oat2/Slc22a7), organic cation transporter 2 (Oct2/Slc22a2) and 3 (Oct3/Slc22a3), ABC-transporters Mdr1 (Pgp/Abcb1) and Mrp4/Abcc4, and peptide transporter 2 (Pept2/Slc15a2) at 48 h and day 7 after i.v. injection of s-GOs and l-GOs at doses of 1, 5, 15 mg/kg bw (n = 3). *p < 0.05, **p < 0.01 and ***p < 0.001 indicate the statistical difference between treated group and the controls. ^#p < 0.05, ^##p < 0.01 and ^###p < 0.001 indicate the statistical difference between s-GO and l-GO treated groups