[Inhibition of liver lysosomal cholesterol esterase activity in rats by dextran blue in vivo and in vitro].
Dextran blue decreases the activity of lysosomal acid cholesteryl esterase of rat liver at a concentration from 0.25 M to 10 M without altering acid phosphatase, acid beta-galactosidase and beta-glucosidase activities. The dextran blue filled lysosomes with a high degree of purity prepared by centrifugation over the linear sucrose density gradient contained insignificant impurities (up to 19%) of protein from other organelles. The specific activity of acid phosphatase, beta-galactosidase and beta-glucosidase was increased 35-40-fold in this fraction, whereas the activity of acid cholesteryl esterase rose but 14.7-fold. Chromatography on a Sepharose 2B column of the digitonin-digested native and dextran-containing lysosomes attests to the formation of large dextran aggregates with lysosomal matrix proteins. Since aggregation of dextran blue with acid phosphatase, beta-galactosidase and beta-glucosidase does not affect their activities, it is concluded that to bring about hydrolysis of lipoprotein cholesterol esters, it is necessary that cholesteryl esterase be associated with hydrophobic macromolecules. Moreover, dextran blue can be used for simulation cholesterol esters deposition in lysosomes.
M I
MI
Dushkin
A V
AV
Dolgov
Iu P
IuP
Nikitin
D000818:Animals; D002265:Carboxylic Ester Hydrolases / Q000037:antagonists & inhibitors*; D002850:Chromatography, Gel; D004396:Coloring Agents / Q000494:pharmacology*; D003911:Dextrans / Q000494:pharmacology*; D066298:In Vitro Techniques; D008099:Liver / Q000032:analysis / Q000201:enzymology*; D008247:Lysosomes / Q000032:analysis / Q000201:enzymology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D002787:Sterol Esterase / Q000032:analysis / Q000037:antagonists & inhibitors*
D004396:Coloring Agents; D003911:Dextrans; C017080:blue dextran; D002265:Carboxylic Ester Hydrolases; D002787:Sterol Esterase
Ingibirovanie aktivnosti lizosomnoĭ kholesterolésterazy pecheni krysdekstranom sinim in vivo i in vitro.