Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2008-8-15
pubmed:abstractText
The large interspecies differences of hepatobiliary transport present a challenge for the allometric prediction of human biliary excretion for drug candidates primarily cleared via hepatobiliary secretion. In the present study, we determined the metabolic stabilities of common fluorescent substrates of hepatobiliary efflux transporters and developed a rapid efflux assay to determine the functional activities of MRP/Mrp, BCRP/Bcrp and P-gp in hepatocytes of four species. The specificities of transporter-mediated dye efflux were confirmed by selective transporter inhibitors. Among tested species, transporter-specific dye efflux kinetics was consistent between freshly isolated and cryopreserved hepatocytes. Hepatocyte elimination half-lives of MRP/Mrp substrates GS-MF and calcein were observed in the rank order of human>monkey>dog>rat. The fourfold higher MRP/Mrp substrate efflux rate of rat hepatocytes compared to human is likely due to the species-specific functional differences of MRP2/Mrp2 expressed on the canalicular membrane. We also observed efficient BCRP-mediated pheophorbide A (PhA) efflux by human and dog hepatocytes, while PhA extrusion in monkey and rat hepatocytes appeared limited. P-gp function measured by DiOC2(3) efflux was minimal in hepatocytes of all origins and no significant species differences were detected. Our results demonstrated marked differences in hepatocyte MRP/Mrp and BCRP/Bcrp activities across species, indicating that they may contribute to the species differences of in vivo hepatobiliary excretion. These results also suggest the potential utility of primary hepatocytes, either fresh or cryopreserved, as an in vitro model to predict interspecies differences in the biliary transport of MRP/Mrp and BCRP/Bcrp substrates.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0928-0987
pubmed:author
pubmed:issnType
Print
pubmed:day
2
pubmed:volume
35
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
114-26
pubmed:meshHeading
pubmed-meshheading:18639632-Animals, pubmed-meshheading:18639632-Bile, pubmed-meshheading:18639632-Carbocyanines, pubmed-meshheading:18639632-Carrier Proteins, pubmed-meshheading:18639632-Cell Separation, pubmed-meshheading:18639632-Cryopreservation, pubmed-meshheading:18639632-Dogs, pubmed-meshheading:18639632-Female, pubmed-meshheading:18639632-Fluoresceins, pubmed-meshheading:18639632-Fluorescent Dyes, pubmed-meshheading:18639632-Half-Life, pubmed-meshheading:18639632-Hepatocytes, pubmed-meshheading:18639632-Humans, pubmed-meshheading:18639632-Macaca fascicularis, pubmed-meshheading:18639632-Male, pubmed-meshheading:18639632-Microsomes, Liver, pubmed-meshheading:18639632-P-Glycoprotein, pubmed-meshheading:18639632-Rats, pubmed-meshheading:18639632-Rats, Sprague-Dawley, pubmed-meshheading:18639632-Species Specificity
pubmed:year
2008
pubmed:articleTitle
Identification of interspecies difference in efflux transporters of hepatocytes from dog, rat, monkey and human.
pubmed:affiliation
Department of Pharmacokinetics, Pfizer Global Research & Development, St. Louis, MO, USA.
pubmed:publicationType
Journal Article, Comparative Study, In Vitro