ArticlePharmaceutical research2003
In vitro polarized transport of L-phenylalanine in human nasal epithelium and partial characterization of the amino acid transporters involved.
Article in Pharmaceutical research, 2003. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.
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Who cites it
2 citing papers in PubMed, 14 citations in OpenAlex.
- Different Culture Conditions Affect Drug Transporter Gene Expression, Ultrastructure, and Permeability of Primary Human Nasal Epithelial Cells.Pharmaceutical research · 2020Article
- Permeation and systemic absorption of R- and S-baclofen across the nasal mucosa.Journal of pharmaceutical sciences · 2011Article
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Authors and funding
9 authors at 2 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
purposeThe purpose of this study was to provide functional and molecular evidence to support the existence of large neutral amino acid transporters in human nasal epithelium using nasal primary cell culture model.
methodsL-Phenylalanine was used as a model substrate to characterize carrier-mediated permeation of amino acids across human nasal epithelium. The influence of temperature, concentration, other amino acids, metabolic/transport inhibitors, and polarity/stereo-selectivity on transport of the model compound was investigated. Reverse transcriptase polymerase chain reaction was used for molecular characterization of the existence of the transporters.
resultsThe transport of L-phenylalanine across the human nasal epithelium was polarized (apical --> basolateral >> basolateral --> apical), saturable (Km = 1.23 mM; Vmax = 805.1 nmol/mg protein/min) and stereo-selective (permeation of L-phenylalanine >> D-Phenylalanine). Its permeation was significantly (< 0.05) reduced by cationic, small and large neutral amino acids, oubain, amiloride, sodium-free medium, and temperature lowering. Reverse transcriptase polymerase chain reaction revealed the presence of the broad-scope cationic-dependent amino acid transporter gene (y+LAT-2) in the human nasal epithelium.
conclusionsBased on the results of this study, one may postulate that the human nasal epithelium expresses L-amino acid transporters. More studies are necessary for detailed characterization of the transporters.
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