Organic anion-transporting polypeptide 2B1 (OATP2B1) is co-localized with OATP1B1 and OATP1B3 in the basolateral hepatocyte membrane, where it is thought to contribute to the hepatic uptake of drugs. We characterized a novel
Slco2b1(-/-) mouse model using positron emission tomography (PET) imaging with
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Organic anion-transporting polypeptide 2B1 (OATP2B1) is co-localized with OATP1B1 and OATP1B3 in the basolateral hepatocyte membrane, where it is thought to contribute to the hepatic uptake of drugs. We characterized a novel
Slco2b1(-/-) mouse model using positron emission tomography (PET) imaging with [
11C]erlotinib (a putative OATP2B1-selective substrate) and planar scintigraphic imaging with [
99mTc]mebrofenin (an OATP1B1/1B3 substrate, which is not transported by OATP2B1). Dynamic 40-min scans were performed after intravenous injection of either [
11C]erlotinib or [
99mTc]mebrofenin in wild-type and
Slco2b1(-/-) mice. A pharmacokinetic model was used to estimate the hepatic uptake clearance (CL
1) and the rate constants for transfer of radioactivity from the liver to the blood (
k2) and excreted bile (
k3). CL
1 was significantly reduced in
Slco2b1(-/-) mice for both radiotracers (
p < 0.05), and
k2 was significantly lower (
p < 0.01) in
Slco2b1(-/-) mice for [
11C]erlotinib, but not for [
99mTc]mebrofenin. Our data support previous evidence that OATP transporters may contribute to the hepatic uptake of [
11C]erlotinib. However, the decreased hepatic uptake of the OATP1B1/1B3 substrate [
99mTc]mebrofenin in
Slco2b1(-/-) mice questions the utility of this mouse model to assess the relative contribution of OATP2B1 to the liver uptake of drugs which are substrates of multiple OATPs.
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