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. 1987 Dec 15;248(3):993–996. doi: 10.1042/bj2480993

Role of reversible phosphorylation in mediating changes in the activity of hepatic 3-hydroxy-3-methylglutaryl-CoA reductase during pregnancy and lactation in the rat.

R A Easom 1, V A Zammit 1
PMCID: PMC1148652  PMID: 3435498

Abstract

1. The expressed and total (completely dephosphorylated) activities of 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase were measured in microsomal fractions isolated from cold-clamped liver samples from female rats in various stages of the reproductive cycle. 2. There was little change in total HMG-CoA reductase activity during pregnancy and early lactation, but after 2 days post partum there was a marked increase in total activity. 3. The expressed/total activity ratio of HMG-CoA reductase showed a profound decrease during the last 2 days of pregnancy. The fraction of the enzyme in the active form increased progressively during the first 2 days of lactation. 4. The combined effect of these changes was that the expressed activity of HMG-CoA reductase changed in parallel with the known changes in the hepatic rate of cholesterogenesis during pregnancy and lactation in vivo.

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Selected References

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