The effect of methylated beta-cyclodextrins on the tight junctions of the rat nasal respiratory epithelium: electron microscopic and confocal laser scanning microscopic visualization studies
| Autor: | Henk K. Koerten, J. van der Meulen, Jan Verhoef, E. Marttin, Nagelkerke Jf, F Spies, Frans W. H. M. Merkus |
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| Rok vydání: | 1999 |
| Předmět: |
Male
Pathology medicine.medical_specialty Confocal Pharmaceutical Science Biology Epithelium law.invention Tight Junctions Confocal microscopy law medicine Animals Rats Wistar Administration Intranasal Cyclodextrins Microscopy Confocal Tight junction beta-Cyclodextrins Actins Rats Nasal Absorption Microscopy Electron Nasal Mucosa medicine.anatomical_structure Paracellular transport Biophysics Respiratory epithelium Nasal administration |
| Zdroj: | Journal of controlled release : official journal of the Controlled Release Society. 57(2) |
| ISSN: | 0168-3659 |
| Popis: | The nasal absorption enhancer randomly methylated β-cyclodextrin (RAMEB) is thought to increase the paracellular permeability of the nasal epithelium by opening of the tight junctions. The effects of RAMEB on the cytoskeleton of the rat nasal epithelium in vivo were determined by confocal laser scanning microscopy (CLSM). The effects on the tight junctions of the rat nasal epithelium were also investigated, using transmission electron microscopy (TEM) of thin sections. The effects of RAMEB were compared with those of the absorption enhancer sodium taurodihydrofusidate (STDHF). Fifteen minutes after nasal administration of 2% RAMEB in vivo, the distribution of cytoskeletal actin was comparable to the untreated control, suggesting that RAMEB does not cause opening of the tight junctions via cytoskeletal interactions. In contrast, administration of 1% STDHF resulted in changes in the actin staining. Furthermore, with TEM severe damage of the nasal epithelium was observed after treatment with 1% STDHF. Ultrastructural changes of the tight junctions were not apparent in TEM sections after treatment with 2% RAMEB. In conclusion, CLSM and TEM are suitable methods to visualize the effects of absorption enhancers on nasal epithelial morphology. |
| Databáze: | OpenAIRE |
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