ISSN:
1573-4935
Keywords:
rat hepatocyte
;
acetoacetyl-CoA ligase
;
HMG-CoA reductase
;
cholesterol synthesis
;
25-hydroxycholesterol
;
high density lipoprotein
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
Notes:
Abstract The activity of acetoacetyl-CoA (AcAc-CoA) ligase (E.C.6.2.1.16) in hepatocytes from rats was shown to be the same as the activity in homogenates of their livers. In hepatocytes treated with 25-hydroxycholesterol, AcAc-CoA ligase, 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase and rates of sterol synthesis were substantially decreased. Hepatocytes treated with high density lipoprotein (HDL) exhibited a 2 to 4 fold induction of HMG-CoA reductase activity; however an accompanying increase in AcAc-CoA ligase activity and the rate of cholesterol synthesis was not observed. We conclude (a) that increases in the activity of HMG-CoA reductase when mediated by HDL in hepatocytes do not result in a corresponding change in the capacity for sterol synthesis and (b) that changes in the activity state of HMG-CoA reductase can be dissociated from that of AcAc-CoA ligase.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01124792
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