Regulation of squalene synthetase activity in rat liver: Elevation by cholestyramine, but no diurnal variation
article
Squalene synthetase activity in liver microsomes from rats sacrificed at three different times of the diurnal cycle showed no significant differences. Addition of 4% cholestyramine to the food resulted in a marked increase in activity (280% of control), independent of the time of killing. 3-Hydroxy-3-methylglutaryl coenzyme A reductase and cholesterol 7??-hydroxylase activity, determined as positive controls, were also found to be elevated by cholestyramine and additionally showed a diurnal variation. On the other hand, five control enzyme activities, not directly related to cholesterol metabolism, i.e. glutamate dehydrogenase, NADPH cytochrome-c reductase, ??-hexosaminidase, catalase and acyl coenzyme A oxidase, showed neither an influence of cholestyramine feeding nor a time of sacrifice dependent variation.
Chemicals/CAS: colestyramine, 11041-12-6, 58391-37-0; beta-N-Acetylhexosaminidase, EC 3.2.1.52; Catalase, EC 1.11.1.6; Cholesterol 7-alpha-Hydroxylase, EC 1.14.13.17; Cholestyramine, 11041-12-6; Glutamate Dehydrogenase, EC 1.4.1.2; Hexosaminidases, EC 3.2.1.-; Hydroxymethylglutaryl CoA Reductases, EC 1.1.1.-; NADPH-Ferrihemoprotein Reductase, EC 1.6.2.4; Oxidoreductases, EC 1.; Squalene Synthetase, EC 1.3.-; Squalene, 111-02-4
Chemicals/CAS: colestyramine, 11041-12-6, 58391-37-0; beta-N-Acetylhexosaminidase, EC 3.2.1.52; Catalase, EC 1.11.1.6; Cholesterol 7-alpha-Hydroxylase, EC 1.14.13.17; Cholestyramine, 11041-12-6; Glutamate Dehydrogenase, EC 1.4.1.2; Hexosaminidases, EC 3.2.1.-; Hydroxymethylglutaryl CoA Reductases, EC 1.1.1.-; NADPH-Ferrihemoprotein Reductase, EC 1.6.2.4; Oxidoreductases, EC 1.; Squalene Synthetase, EC 1.3.-; Squalene, 111-02-4
Topics
colestyramineenzymesqualene synthetaseanimal experimentdose time effect relationlivernonhumanoral drug administrationpriority journalratAnimalbeta-N-AcetylhexosaminidaseCatalaseCholesterol 7-alpha-HydroxylaseCholestyramineCircadian RhythmGlutamate DehydrogenaseHexosaminidasesHydroxymethylglutaryl CoA ReductasesMaleMicrosomes, LiverNADPH-Ferrihemoprotein ReductaseOxidoreductasesRatsRats, Inbred StrainsSqualeneSqualene Synthetase
TNO Identifier
230063
ISSN
0006291X
Source
Biochemical and Biophysical Research Communications, 138(1), pp. 335-341.
Pages
335-341
Files
To receive the publication files, please send an e-mail request to TNO Repository.