| Heparin decreases permeability of pig urinary bladder wall preliminarily enhanced by chitosan. | |
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MedLine Citation:
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PMID: 18302041 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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Chitosan significantly increases the permeability of the isolated pig urinary bladder wall by causing urothelial desquamation, the extent of which depends also on the concentration of the polymer. By desquamation permeability barriers of the urothelium are removed. To gain additional insight into the mechanism by which chitosan acts an absorption enhancer into urinary bladder mucosa, we evaluated the influence of a polysaccharide heparin on the permeability of isolated pig urinary bladder wall preliminarily treated with chitosan. Moreover, we aimed to establish whether the effect of heparin depends on its concentration and on the degree of urothelial desquamation caused by chitosan. In the permeability studies performed by the use of diffusion cells, transport of a model drug, pipemidic acid, into the isolated pig urinary bladder wall was determined. Heparin did not have a significant effect on the permeability of the intact urothelium. When applied to the urinary bladder wall, whose permeability was preliminarily enhanced by 0.005% or 0.001% w/v chitosan, heparin decreased the permeation of pipemidic acid into the bladder wall to a level not significantly different from the intact tissue. However, the effect of heparin was not significant at the highest concentration of chitosan tested, where the damage to the urothelium was much more intense compared with that found at lower concentrations of the polymer. The formation of complexes between pipemidic acid and heparin cannot be excluded completely, but it seems that they are not the main reason for the decreased permeation of pipemidic acid in the presence of heparin. By application on the urothelium, damaged by chitosan, heparin is supposed to form a layer on the surface of the urothelium that prevents the transport of the model drug into the bladder wall. In this way heparin probably restores the impermeability properties of the urinary bladder wall to a degree dependent on the urothelial damage. |
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Authors:
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Mojca Kerec Kos; Marija Bogataj; Ales Mrhar |
Publication Detail:
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Type: In Vitro; Journal Article |
Journal Detail:
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Title: Drug development and industrial pharmacy Volume: 34 ISSN: 0363-9045 ISO Abbreviation: Drug Dev Ind Pharm Publication Date: 2008 Feb |
Date Detail:
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Created Date: 2008-02-27 Completed Date: 2008-05-20 Revised Date: - |
Medline Journal Info:
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Nlm Unique ID: 7802620 Medline TA: Drug Dev Ind Pharm Country: United States |
Other Details:
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Languages: eng Pagination: 215-20 Citation Subset: IM |
Affiliation:
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Faculty of Pharmacy, University of Ljubljana, Slovenia. |
Export Citation:
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APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
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Absorption Animals Chitosan / pharmacology* Dose-Response Relationship, Drug Heparin / pharmacology* Permeability Pipemidic Acid / pharmacokinetics Swine Urinary Bladder / metabolism* Urothelium / metabolism |
| Chemical | |
Reg. No./Substance:
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51940-44-4/Pipemidic Acid; 9005-49-6/Heparin; 9012-76-4/Chitosan |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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