A polarized localization of amino acid/carnitine transporter B(0,+) (ATB(0,+)) in the blood-brain barrier.
Brain capillary endothelial cells control the uptake and efflux from the brain of many hydrophilic compounds due to highly specialized transporters often localized in a polarized way. Localization of Na(+)- and Cl(-)-dependent amino acid and carnitine transporter B(0,+) (ATB(0,+)) was studied in a co-culture of bovine brain capillary endothelial cells (BBCEC) grown on filters above astrocytes (an in vitro blood-brain barrier model). Immunoblotting and three-dimensional immunocytochemistry analysis with anti-B(0,+)antibodies demonstrated the presence of this transporter and its prevalent co-localization with P-glycoprotein i.e. at the apical side. The sensitivity of leucine uptake through the apical membrane to 2-aminobicyclo-[2.2.1]-heptane-2-carboxylic acid (BCH), D-serine as well as sodium and chloride replacement confirm the functioning of ATB(0,+) and suggests an important physiological role of ATB(0,+) in controlling the delivery of amino acids and carnitine to the brain.
Czeredys
Magdalena
M
Nencki Institute of Experimental Biology, Department of Molecular and Cellular Neurobiology, 3 Pasteur Street, 02-093 Warszawa, Poland.
Mysiorek
Caroline
C
Kulikova
Natalia
N
Samluk
Łukasz
Ł
Berezowski
Vincent
V
Cecchelli
Roméo
R
Nałecz
Katarzyna A
KA
D026962:Amino Acid Transport System ASC / Q000378:metabolism*; D026921:Amino Acid Transport Systems, Neutral / Q000378:metabolism*; D000598:Amino Acids, Cyclic / Q000494:pharmacology; D000818:Animals; D001812:Blood-Brain Barrier / Q000187:drug effects / Q000378:metabolism*; D002331:Carnitine / Q000378:metabolism; D002417:Cattle; D007930:Leucine / Q000378:metabolism; D051381:Rats
D026962:Amino Acid Transport System ASC; D026921:Amino Acid Transport Systems, Neutral; D000598:Amino Acids, Cyclic; C006504:2-aminobicyclo(2,2,1)heptane-2-carboxylic acid; D007930:Leucine; D002331:Carnitine