Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1993-10-21
pubmed:abstractText
Low molecular weight proteins (LMWPs) are potential carriers for targeting drugs to the kidney. To test whether ester bonds are suitable for the reversible drug conjugation, the antiinflammatory drug naproxen (Nap) was conjugated to the LMWP lysozyme (LYSO) via an ester bond using an L-lactic acid spacer (Nap-lact-LYSO, 1:1:1). The distribution and degradation of the conjugate in rats were compared to those of an equimolar mixture of free drug and LMWP and of a directly coupled conjugate without spacer (Nap-LYSO). The plasma clearance of Nap-lact-LYSO closely resembled that of Nap-LYSO and LYSO itself. Its major accumulation site appeared to be the kidney as demonstrated by extracorporal gamma-camera counting of the LMWP. Renally released naproxen was excreted in the urine as 6-desmethyl-naproxen-sulfate (6-DMN-S). Apparently the kidneys represent the main sites of demethylation and sulfation after administration of the LMWP-coupled drug. In addition, the renal excretion of naproxen (including its metabolites) was significantly delayed and sustained as compared to that after injection of uncoupled naproxen. Using the L-lactic acid spacer LMWP conjugation, the renal selectivity of Nap was increased 5.6 +/- 0.41-fold. Additional in vitro studies with Nap-lact-LYSO revealed that renal generation of the parent drug coincided with formation of low molecular weight catabolites, mainly as naproxen-L-lactic acid-lysine (Nap-lact-Lys). This indicated that in vitro the rate of cleavage of the ester bond is significantly slower than digestion of the carrier backbone itself.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0724-8741
pubmed:author
pubmed:issnType
Print
pubmed:volume
10
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
963-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Low molecular weight proteins as carriers for renal drug targeting: naproxen coupled to lysozyme via the spacer L-lactic acid.
pubmed:affiliation
University Center for Pharmacy, Department of Pharmacology and Pharmacotherapy, Groningen, The Netherlands.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't