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Updated: Aug 18, 2026

Ovariectomy and 17β-estradiol Replacement in Rats and Mice: A Visual Demonstration
Published on: June 7, 2012
[Estradiol-induced formation of the polyribosomal complex synthesizing ceruloplasmin in rats]
Abstract:
The effects of estradiol on the oxidase activity of ceruloplasmin (CP) in rat serum and on the relative content of nascent CP chains in rat liver polyribosomes were studied. Using radioimmunological methods, it was shown that a 2--3-fold increase of the oxidase activity of CP in the blood induced by estradiol is accompanied by an increase in the amount of nascent CP chains in the polyribosomes. On the 5th, 8th, 10th and 11th post-injection days the binding of specific anti-CP 125I-immunoglobulins to the polyribosomes is increased by 17, 28, 70 and 95%, respectively. The values of sedimentation coefficients for the CP-synthesizing polyribosomes in the control and under estradiol induction are identical and make up to 425--430S. It is concluded that the increase of the oxidase activity of CP in the serum is due to stimulation of the de novo synthesis of CP rather than to the activation of the protein molecules.
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