Brain-to-blood active transport of beta-alanine across the blood-brain barrier.
A high-affinity antiluminal uptake system for beta-alanine was demonstrated in primary cultured bovine brain capillary endothelial cells (BCEC) for which K(t) is 66.9 microM. beta alanine uptake was energy-, sodium- and chloride ion-dependent. beta-amino acids strongly inhibited the uptake, while alpha- and gamma-amino acids had a little or no inhibitory effect. In ATP-depleted cells, the uptake was stimulated by preloading beta-alanine or taurine but not by L-leucine. These results suggest that beta-alanine is actively transported across the antiluminal membrane of BCECs that is common to beta-amino acids. The system may function for the efflux from the brain to blood.
Komura
J
J
Division of Life Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Japan.
Tamai
I
I
Senmaru
M
M
Terasaki
T
T
Sai
Y
Y
Tsuji
A
A
D000596:Amino Acids / Q000494:pharmacology; D000818:Animals; D001386:Azides / Q000494:pharmacology; D001812:Blood-Brain Barrier / Q000187:drug effects; D001921:Brain / Q000378:metabolism; D002417:Cattle; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000378:metabolism; D007477:Ions; D010042:Ouabain / Q000494:pharmacology; D019810:Sodium Azide; D013696:Temperature; D013997:Time Factors; D014475:Uncoupling Agents / Q000494:pharmacology; D015091:beta-Alanine / Q000031:analogs & derivatives / Q000097:blood / Q000378:metabolism*
D000596:Amino Acids; D001386:Azides; D007477:Ions; D014475:Uncoupling Agents; D015091:beta-Alanine; D010042:Ouabain; D019810:Sodium Azide