Shift from Biliary to Urinary Elimination of Acetaminophen-Glucuronide in Acetaminophen-Pretreated Rats

Abstract

Despite its toxicity, acetaminophen (APAP) is used increasingly as an analgesic, antipyretic, and anti-inflammatory agent. We examined the effect of prior exposure to APAP on its biliary and urinary elimination. The biliary and urinary elimination of a test dose of APAP (150 mg/kg i.v.) was determined in male Wistar rats 24 h after pretreatment with vehicle, a single dose (1.0 g/kg i.p.), or increasing daily doses (0.2, 0.3, 0.6, and 1.0 g/kg/day i.p.) of APAP. Although elimination of the parent APAP was minimally affected, biliary excretion of APAP glucuronide was significantly decreased 70 and 80%, whereas urinary excretion was significantly increased 90 and 100% in the groups pretreated with single and repeated doses of APAP, respectively, relative to vehicle controls. Western analysis and confocal immunofluorescent microscopy indicated a marked increase in hepatic expression of multidrug resistance-associated protein 3 (Mrp3) in both groups pretreated with APAP, relative to expression of Mrp2. ATP-dependent transport of [ 3 H]taurocholate, an Mrp3 substrate, was significantly increased in basolateral liver plasma membrane vesicles from rats pretreated with repeated doses of APAP relative to controls. Enterohepatic recirculation of APAP glucuronide after administration of the same test dose of the drug was significantly decreased in rats pretreated with repeated doses of APAP. These data indicate that APAP pretreatment induced a shift from biliary to urinary elimination of APAP glucuronide, consistent with the increased expression of Mrp3 in the basolateral domain of the hepatocyte. We postulate that decreased enterohepatic recirculation contributes to decreased APAP hepatotoxicity by reducing liver exposure.

Xenobiotic, Bile Acid, and Cholesterol Transporters: Function and Regulation

“…This hypothesis is supported by the fact that Kupffer cells participate not only in protecting the liver from APAP toxicity but also in upregulating hepatocellular Mrp4 protein (Campion et al, 2008). Work by Ghanem et al (2005) has provided an additional explanation for APAP autoprotection in rodents. Pretreatment of rats with increasing doses of APAP alters the excretion of the final high dose of APAP and corresponds to reduced hepatotoxicity (compared with rats receiving only the high dose).…”

Beneficial Effect of Spironolactone Administration on Ethynylestradiol-Induced Cholestasis in the Rat: Involvement of Up-Regulation of Multidrug Resistance-Associated Protein 2

“…Western blot analyses of Mrp2, Bsep, and AE2 were performed in MPM as described . Detection of Mrp3 was performed also in MPM using a rabbit polyclonal antibody to rat Mrp3 (Ogawa et al, 2000), as previously described (Ghanem et al, 2005). Detection of UDP-glucuronosyltransferases (UGTs) was performed in microsomal preparations using polyclonal anti-peptide antibodies that specifically recognize the 1A6 and 1A7 isoforms belonging to UGT family 1 (Ikushiro et al, 1995), as previously reported (Luquita et al, 2001).…”

“…Liver viability was controlled throughout by monitoring LDH leakage into the perfusate (with values Ͻ10 IU/l between the start and the end of the experiment). The content of APAP-glu in bile, perfusate, and liver homogenate was determined by HPLC (Ghanem et al, 2005). UGT Activity.…”

Role of Transporters in the Disposition of the Selective Phosphodiesterase-4 Inhibitor (+)-2-[4-({[2-(Benzo[1,3]dioxol-5-yloxy)-pyridine-3-carbonyl]-amino}-methyl)-3-fluoro-phenoxy]-propionic Acid in Rat and Human

“…This finding was consistent with the observation that reduced biliary excretion was compensated to some extent by an increase in the renal clearance of CP-671,305 potentially due to adaptive changes in expression of other transporters in TR Ϫ rats. For example, it is known that the hepatic expression of Mrp3, which also mediates transport of organic anions across the hepatocyte basolateral membrane into sinusoidal blood, is significantly up-regulated in Mrp2-deficient rats (Hirohashi et al, 1998) and has been speculated to play a role in a compensatory shift from biliary to renal elimination for organic anions such as a acetaminophenglucuronide (Ghanem et al, 2005) and pravastatin (Kivistö et al, 2005). Whether CP-671,305 is a substrate for human and rat MRP3/ Mrp3 remains to be evaluated.…”