Pharmaceutical Research

, Volume 23, Issue 11, pp 2515–2524 | Cite as

Micronutrient and Urate Transport in Choroid Plexus and Kidney: Implications for Drug Therapy

  • Reynold Spector
  • Conrad JohansonEmail author



With application of molecular biology techniques, there has been rapid progress in understanding how many drugs and micronutrients (e.g., vitamins) are transferred across the choroid plexus (CP), the main transport locus of the blood–cerebrospinal fluid (CSF) barrier, and the renal tubular epithelial cells. In many cases, these molecules are transported by separate, specific carriers or receptors on the apical and/or basal side of the CP or renal epithelial cells. This commentary focuses on four micronutrient transport systems in CP (ascorbic acid, folate, inositol, and riboflavin), all of which have been recently cloned, expressed and for which knockout mice models were developed and transporter localization studies performed. Also reviewed is the recently cloned uric acid transport system in human kidney in which there exists a human “knockout” model. The implications of these transport systems for drug therapy of central nervous system and renal disorders are discussed, especially with regard to methods to circumvent the blood–brain and blood–CSF barriers to deliver drugs to the brain.

Key words

ascorbic acid blood–brain barrier blood–cerebrospinal fluid (CSF) barrier choroid plexus epithelium folate folate receptor (FRα) inositol myo-inositol cotransporter (SMIT 1) organic acid transporter 3 (OAT 3) penicillin riboflavin sodium ascorbate cotransporter (SVCT 2) uric acid transporter (URAT 1) vitamin homeostasis 


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Copyright information

© Springer Science + Business Media, Inc. 2006

Authors and Affiliations

  1. 1.Robert Wood Johnson Medical SchoolNew BrunswickUSA
  2. 2.Harvard-MIT Program in the Health SciencesCambridgeUSA
  3. 3.Brown Medical SchoolProvidenceUSA
  4. 4.Dept. of NeurosurgeryRhode Island HospitalProvidenceUSA

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