Organic-Anion-Transporting Peptide OATP

D-Ala-deltorphin-I and -II transverse the blood brain barrier in vivo and in vitro [51]. Recently, D-Ala-deltorphin-II was identified as a transport substrate of organic anion transporting polypeptides (Oatp/OATP), a family of polyspecific membrane transporters, strongly expressed at the rat and human blood brain barrier [52]. Modified analogues of these peptides were synthesized to improve their transit across the blood brain barrier [48,49,53]. Because they resist enzyme degradation and can cross endothelial barriers into the CNS, the deltorphins meet the criteria for peptides with potential for systemic administration. 

Letschert, K., Komatsu. M., Hummel-Eisenbeiss, J., and Keppler, D. (2005) Vectorial transport of the peptide CCK-8 by double-transfected MDCKII cells stably expressing the organic anion transporter OATP1B3 (OATPS) and the export pump ABCC2. The Journal of Pharmacology and Experimental Therapeutics, 313 (2), 549-556. 

The drug uptake (SLC) family of transporter is the largest superfamily of transporters. This family includes 31 transporters from organic anion transporter polypeptides (OATPs), organic anion transporters (OATs), organic cation transporters (OCTs), peptide cotransporters (PEPTs), and sodium-bile acid cotransporter classes. Only OATP, OAT, OCT, and PEPT are primarily involved with the transport of drugs/xenobiotics. 

The organic anion transporters (human OATs, rodent oats) are classified within the SLC22A solute carrier family, and the transporting peptides (human OATPs, rodent... 

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