Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1985-6-11
pubmed:abstractText
An isolated perfused rat liver system was used to study the hepatic uptake and degradation of asialo orosomucoid (asialo alpha 1-acid glycoprotein). To this aim we coupled the fluorochrome FITC to the asialoglycoprotein. The covalent attachment of FITC to the glycoprotein did not affect its perfusate disappearance. The disappearance rate was characterized by a t1/2 approximately equal to 6.1 min, the clearance being 11.2 ml/min. The internalized ligand was probably extensively degraded in the lysosomes as demonstrated by the appearance of low molecular weight fluorescent compounds in the bile, having a higher fluorescence yield than the native conjugate. Lysosomal degradation of ASOR-FITC was shown to be the rate limiting step in FITC excretion into the bile. Treatment of a perfused liver with varying doses of the protease inhibitor leupeptin did not influence the perfusate disappearance rate of the protein. However, leupeptin inhibited the biliary output of FITC metabolites in a dose dependent fashion, half maximal inhibition occurring at 210 nM (in the perfusion medium), corresponding with a dose of 0.05 mg leupeptin per 10 g liver. It is concluded that the rate of lysosomal degradation of proteins in vivo can be determined by measuring the biliary excretion of fluorescent material originating from fluorescent probes covalently coupled to the particular protein.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0006-2952
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
34
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1399-405
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Biliary excretion of FITC metabolites after administration of FITC labeled asialo orosomucoid as a measure of lysosomal proteolysis.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't