Localization of the organic anion transporting polypeptide 2 (Oatp2) in capillary endothelium and choroid plexus epithelium of rat brain.
In this study we investigated the distribution of a recently cloned polyspecific organic anion transporting polypeptide (Oatp2) in rat brain by nonradioactive in situ hybridization histochemistry and immunofluorescence microscopy. The results demonstrate that Oatp2 is expressed in brain capillary and in plexus epithelial cells. At the blood-brain barrier (BBB), Oatp2 expression could be co-localized with the endothelial marker vWF (von Willebrand factor) but not with the astrocyte marker GFAP (glial fibrillary acidic protein). In choroid plexus epithelial cells, Oatp2 could be localized to the basolateral cell pole, whereas the first member of the Oatp gene family of membrane transporters to be cloned (Oatp1) co-localized with the alpha(1)-subunit of Na,K-ATPase at the apical plasma membrane domain. Because Oatp1 and Oatp2 have been previously shown to mediate transmembrane transport of a wide variety of amphipathic organic compounds, including many drugs and other xenobiotics, the histochemical localization of Oatp2 at the BBB and of Oatp1 and Oatp2 in the choroid plexus imply a role for these transporters in the active exchange of amphipathic solutes between the blood, brain, and cerebrospinal fluid compartments. (J Histochem Cytochem 47:1255-1263, 1999)
Gao
B
B
Division of Clinical Pharmacology and Toxicology, Department of Medicine, University Hospital, and Institute of Pharmacology, University of Zurich, Zurich, Switzerland.
Stieger
B
B
Noé
B
B
Fritschy
J M
JM
Meier
P J
PJ
D000818:Animals; D027321:Anion Transport Proteins; D015153:Blotting, Western; D001921:Brain / Q000098:blood supply* / Q000378:metabolism; D002196:Capillaries / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism*; D002831:Choroid Plexus / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000378:metabolism*; D019084:Fluorescent Antibody Technique, Indirect; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D007124:Immunoenzyme Techniques; D017403:In Situ Hybridization; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D014841:von Willebrand Factor / Q000378:metabolism
D027321:Anion Transport Proteins; D002352:Carrier Proteins; D005904:Glial Fibrillary Acidic Protein; D012333:RNA, Messenger; D014841:von Willebrand Factor; D000254:Sodium-Potassium-Exchanging ATPase