Drug elimination renal

Within the OAT family, OAT4 is the only transporter expressed at appreciable levels in both the placenta and in the kidney [54]. The membrane localization of OAT4 within these tissues has not been examined. Steroid sulfates, and ochratoxinA are efficient transport substrates of OAT4, whereas PAH is weakly transported [54]. The functional importance of OAT4 in regulating placental permeability and renal drug elimination is currently unknown. 

An important pharmacokinetic change that occurs in persons of advanced age is that of reduced renal drug elimination,... 

Lee W, Kim RB. Transporters and renal drug elimination. Annu Rev Pharmacol Toxicol. 2004 44 137-166. 

The maturation of renal drug elimination systems occurs at variable rates and may be influenced by a number of factors, including pre-or postnatal exposure to drugs. In addition, the mechanisms of drug uptake and storage in renal tubular cells are subject to matura-tional changes that may lead to age-related differences in intrarenal accumulation of a drug [8c]. 

Human OCTI is expressed in the liver, kidney (weakly), intestine, and placenta. Like OCTI and OCTI, OCTI appears to support electrogenic potential-sensitive organic cation transport. Some studies have suggested that OCTI is the extraneuronal monoamine transporter based on its substrate specificity and potency of interaction with monoamine neurotransmitters. Because of its relatively low abundance in the kidney, OCTI may play only a limited role in renal drug elimination. 

McLachlan AJ, Gross AS, Beal JL, Minns I, and SE Tett (2001). Analytical validation for a series of marker compounds used to assess renal drug elimination processes. Therapeutic Drug Monitoring 23 39 6. 

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