title: Localization of organic anion transporting polypeptide 3 (oatp3) in mouse brain parenchymal and capillary endothelial cells.
abstract: Organic anion transporting polypeptide 3 (oatp3) transports various CNS-acting endogenous compounds, including thyroid hormones and prostaglandin E2, between extra- and intracellular spaces, suggesting a possible role in CNS function. The purpose of this study was to clarify the expression and localization of oatp3 in the mouse brain. RT-PCR analysis revealed that oatp3 mRNA is expressed in brain capillary-rich fraction, conditionally immortalized brain capillary endothelial cells, choroid plexus, brain and lung, but not in liver or kidney, where oatp1, 2 and 5 mRNAs were detected. Immunohistochemical analysis with anti-oatp3 antibody suggests that oatp3 protein is localized at the brush-border membrane of mouse choroid plexus epithelial cells. Furthermore, intense immunoreactivity was detected in neural cells in the border region between hypothalamus and thalamus, and in the olfactory bulb. Immunoreactivity was also detected in brain capillary endothelial cells in the cerebral cortex. These localizations in the mouse brain suggest that oatp3 plays roles in blood-brain and -cerebrospinal fluid barrier transport of organic anions and signal mediators, and in hormone uptake by neural cells.
authors.affiliation: Department of Molecular Biopharmacy and Genetics, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba-ku, Sendai, Japan.
authors.forename: Sumio
authors.initials: S
authors.lastname: Ohtsuki
authors.forename: Takuya
authors.initials: T
authors.lastname: Takizawa
authors.forename: Hitomi
authors.initials: H
authors.lastname: Takanaga
authors.forename: Satoko
authors.initials: S
authors.lastname: Hori
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Hosoya
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Terasaki
mesh_terms: D000818:Animals; D001812:Blood-Brain Barrier / Q000378:metabolism; D015153:Blotting, Western; D001921:Brain / Q000098:blood supply* / Q000166:cytology / Q000378:metabolism*; D002196:Capillaries / Q000166:cytology / Q000378:metabolism*; D002478:Cells, Cultured; D002831:Choroid Plexus / Q000166:cytology / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D009928:Organ Specificity; D027361:Organic Anion Transporters / Q000096:biosynthesis* / Q000235:genetics; D029362:Organic Anion Transporters, Sodium-Independent / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: C489252:Oatp3 protein, mouse; D027361:Organic Anion Transporters; D029362:Organic Anion Transporters, Sodium-Independent; D012333:RNA, Messenger