Linked Life Data

15019073

Source:http://linkedlifedata.com/resource/pubmed/id/15019073

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2004-3-15
pubmed:abstractText
The main objective of the present study was to examine the effect of chemical crosslinking of chitosan microspheres on the gastric residence and local tetracycline concentrations following oral administration in fasted gerbils. Radioiodinated [125I] glyoxal-crosslinked chitosan microsphere suspension in deionized distilled water was administered for the gastric residence studies. At different time points, the animals were sacrificed and the radioactivity in tissues and fluids was measured. Stomach tetracycline concentrations were determined using tritiated-[3H]-tetracycline-loaded crosslinked chitosan microspheres. The radioactivity, measured with a liquid scintillation analyzer, was used to determine the microgram of drug per gram of tissues or fluids. After 2 h in the fasted stomach, approximately 10% of the non-crosslinked chitosan microspheres remained. On the other hand, 17% of the crosslinked chitosan microspheres remained in the fasted stomach after the same time period. The microspheres were predominantly found in the colon after 6 h of administration. There was no detectable radioactivity in the plasma, urine, small intestine, liver, and kidneys. Tetracycline concentration profile in the stomach from the crosslinked microsphere formulation was higher than that of the aqueous solution and the non-crosslinked microsphere formulation. While the area-under-the-curve (AUC(0.5-->10 h)) for tetracycline solution and non-crosslinked chitosan microspheres was 447.3 and 358.2 microg h/g of tissue, respectively, the AUC(0.5-->10 h) for the crosslinked chitosan microspheres was 868.9 microg h/g of tissue. The drug was predominantly found in the colon and urine after 6 h of administration. Results of this study show that chitosan microspheres prepared by chemical crosslinking provide a longer residence time in the fasted gerbil stomach than either tetracycline solution or microspheres prepared by ionic precipitation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0378-5173
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
272
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
99-108
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Stomach-specific anti-H. pylori therapy; part III: effect of chitosan microspheres crosslinking on the gastric residence and local tetracycline concentrations in fasted gerbils.
pubmed:affiliation
Department of Pharmaceutical Sciences, School of Pharmacy, Northeastern University, Boston, MA 02115, USA. Radi71@yahoo.com
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't