Functional analysis of rat renal organic anion transporter OAT‐K1: bidirectional methotrexate transport in apical membrane

FEBS Letters

Masuda, Satohiro¹  Takeuchi, Ayako¹  Inui, Ken-ichi¹  Saito, Hideyuki¹  Hashimoto, Yukiya¹ 

[1] Department of Pharmacy, Kyoto University Hospital, Faculty of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8507, Japan

关键词: Organic anion transporter;    Methotrexate;    Brush-border membrane;    Tubular secretion;    MDCK cell;    (Rat kidney);    RT;    reverse transcription;    PCR;    polymerase chain reaction;    oatp;    organic anion transporting polypeptide;   

DOI  :  10.1016/S0014-5793(99)01221-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Renal organic anion transporter OAT-K1 was stably transfected in MDCK cells and examined for its transport characteristics and membrane localization. OAT-K1 mediated both uptake and efflux of methotrexate in the apical membranes. Immunoblotting showed that the apparent molecular mass of the expressed OAT-K1 was 50 kDa, which was comparable to that found in the rat renal brush-border membranes. The OAT-K1-mediated methotrexate transport was significantly inhibited in the presence of several organic anions such as folate and sulfobromophthalein. These findings suggest that OAT-K1 mediates bidirectional methotrexate transport across the apical membranes, and may be involved in the renal handling of methotrexate.

【 授权许可】

Unknown