title: Transport of acebutolol through rabbit corneal epithelium.
abstract: The purpose of this study is to characterize transport of acebutolol through the corneal epithelium. Cultured normal rabbit corneal epithelial cells (RCEC) were used to investigate the drug transport. Primary RCEC were seeded on a filter membrane of Transwell-COL insert coated with fibronectin and were grown in Dulbecco's modified Eagle's medium/nutrient mixture F-12 with various supplements. Measurements of acebutolol permeability through RCEC layer were carried out to assess transcellular permeability coefficient (P(transcell)) in the absence or presence of inhibitors. Paracellular permeability coefficient (P(paracell)) was calculated by permeability coefficient of hydrophilic drugs (P(cell)). The transcellular permeability of acebutolol from apical side to basal side (A-to-B) showed concentration-dependency. The acebutolol flux in the A-to-B direction was smaller than that of opposite direction. Sodium azide, verapamil, and cyclosporin A enhanced the transcellular permeability of acebutolol in the A-to-B direction. Acebutolol permeability through an excised rabbit cornea was also increased by verapamil. Thus, it was suggested that acebutolol was actively secreted via P-glycoprotein in a corneal epithelium.
authors.affiliation: Nara Research and Development Center, Santen Pharmaceutical Co., Ltd, Ikoma, Japan.
authors.forename: Kouichi
authors.initials: K
authors.lastname: Kawazu
authors.forename: Akemi
authors.initials: A
authors.lastname: Oshita
authors.forename: Tadahiro
authors.initials: T
authors.lastname: Nakamura
authors.forename: Mikiro
authors.initials: M
authors.lastname: Nakashima
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Ichikawa
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Sasaki
mesh_terms: D000070:Acebutolol / Q000378:metabolism*; D000319:Adrenergic beta-Antagonists / Q000378:metabolism*; D000465:Algorithms; D000818:Animals; D002478:Cells, Cultured; D019573:Epithelium, Corneal / Q000378:metabolism*; D066298:In Vitro Techniques; D010539:Permeability; D011817:Rabbits
chemical_list: D000319:Adrenergic beta-Antagonists; D000070:Acebutolol