LIPOPROTEIN RECEPTORS IN COPPER-DEFICIENT RATS: IN VITRO BINDING OF HIGH DENSITY LIPOPROTEIN SUBFRACTIONS TO LIVER MEMBRANES.

Persistent Link:
http://hdl.handle.net/10150/183955
Title:
LIPOPROTEIN RECEPTORS IN COPPER-DEFICIENT RATS: IN VITRO BINDING OF HIGH DENSITY LIPOPROTEIN SUBFRACTIONS TO LIVER MEMBRANES.
Author:
Hassel, Craig Alan
Issue Date:
1986
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Three studies were conducted to determine whether the elevated plasma and HDL cholesterol levels observed in copper-deficient rats could be explained by the interaction of ¹²⁵I-HDL subfractions with liver membrane preparations in vitro. Rats from all studies were randomly divided into two dietary treatments, copper-deficient and adequate (0.7 mg and 8.0 mg Cu/kg diet, respectively). Deionized water and diet were provided ad libitum. After eight weeks, rats were exsanguinated, membranes prepared from livers, and plasma high density lipoproteins (HDL) isolated by ultracentrifugation and agarose column chromatography. Heparin-Sepharose affinity chromatography was used to isolate specific subfractions of HDL. The HDL subfractions derived from rats of each dietary treatment were iodinated and bound to either crude liver membranes or purified liver plasma membranes prepared from rats of both treatment groups. Total binding data and computer derived estimates (K(d) and B(max)) were used to compare differences between treatments. Binding data from all experiments conformed to a one-site model. In all cases, binding was saturable and EDTA and pronase insensitive. Treatment differences were observed in Study I (¹²⁵I-apo E-free HDL binding to crude liver membranes). Significantly lower total binding and B(max) were observed when lipoproteins and membranes from copper-deficient animals were used in the assay. Competition experiments from Studies II and III demonstrate that the different HDL subfractions competed effectively with one another for binding sites, indicating that apo E is not a determinant in binding of rat ¹²⁵I-HDL subfractions to purified liver plasma membranes.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Copper -- Nutrition.; Cholesterol.; High density lipoproteins.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Nutritional Sciences; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Lei, David

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleLIPOPROTEIN RECEPTORS IN COPPER-DEFICIENT RATS: IN VITRO BINDING OF HIGH DENSITY LIPOPROTEIN SUBFRACTIONS TO LIVER MEMBRANES.en_US
dc.creatorHassel, Craig Alanen_US
dc.contributor.authorHassel, Craig Alanen_US
dc.date.issued1986en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractThree studies were conducted to determine whether the elevated plasma and HDL cholesterol levels observed in copper-deficient rats could be explained by the interaction of ¹²⁵I-HDL subfractions with liver membrane preparations in vitro. Rats from all studies were randomly divided into two dietary treatments, copper-deficient and adequate (0.7 mg and 8.0 mg Cu/kg diet, respectively). Deionized water and diet were provided ad libitum. After eight weeks, rats were exsanguinated, membranes prepared from livers, and plasma high density lipoproteins (HDL) isolated by ultracentrifugation and agarose column chromatography. Heparin-Sepharose affinity chromatography was used to isolate specific subfractions of HDL. The HDL subfractions derived from rats of each dietary treatment were iodinated and bound to either crude liver membranes or purified liver plasma membranes prepared from rats of both treatment groups. Total binding data and computer derived estimates (K(d) and B(max)) were used to compare differences between treatments. Binding data from all experiments conformed to a one-site model. In all cases, binding was saturable and EDTA and pronase insensitive. Treatment differences were observed in Study I (¹²⁵I-apo E-free HDL binding to crude liver membranes). Significantly lower total binding and B(max) were observed when lipoproteins and membranes from copper-deficient animals were used in the assay. Competition experiments from Studies II and III demonstrate that the different HDL subfractions competed effectively with one another for binding sites, indicating that apo E is not a determinant in binding of rat ¹²⁵I-HDL subfractions to purified liver plasma membranes.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectCopper -- Nutrition.en_US
dc.subjectCholesterol.en_US
dc.subjectHigh density lipoproteins.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineNutritional Sciencesen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorLei, Daviden_US
dc.contributor.committeememberMarchello, Johnen_US
dc.contributor.committeememberAllen, Ronald E.en_US
dc.contributor.committeememberBerry, Jimen_US
dc.contributor.committeememberReid, Bobbyen_US
dc.identifier.proquest8704771en_US
dc.identifier.oclc698247301en_US
All Items in UA Campus Repository are protected by copyright, with all rights reserved, unless otherwise indicated.