Action of Cyclic Adenosine 3',5'-Monophosphate in Vitro on the Uptake and Incorporation of Uridine into Ribonucleic Acid in Ovariectomized Rat Uterus

Myeloid marrow was rapidly removed from femurs of fasting young rabbits, sectioned, and incubated in Krebs-bicarbonate-CO2-oxygen buffer with appropriate C14-labeled precursors. All manipulations were designed to preserve the architecture of the tissue. After 1 hr the protein or nucleic acid-adenine was isolated and purified. Insulin, 0.01 U/ml added in vitro, stimulated histidine-2(ring)-C14 incorporation into protein by 26 ± 1.4%; alkali-treated insulin was inactive. Thyroxin elicited a 49.4 ± 2.1% stimulation at an optimum concentration of 10–7 m. Triiodothyronine, but not diiodothyronine, also had a significant effect. Insulin increased incorporation of carbon from adenosine-8-C14 into adenine of ribonucleic acid and deoxyribonucleic acid. Thyroxin, on the other hand, was without consistent effect on this process. Thyroxin stimulated significantly the incorporation of C14 of glycine-2-C14 into adenine. The possibility that part of the anabolic effect of thyroxin on bone marrow may arise from a stimulus to incorporation of precursors into purines is suggested.

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In Vitro Transcription of Xenopus Mitochondrial Deoxyribonucleic Acid by Homologous Mitochondrial Ribonucleic Acid Polymerase

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)42434-4 ◽

1974 ◽

Vol 249 (14) ◽

pp. 4412-4419

Author(s):

Guang-Jer Wu ◽

Igor B. Dawid

Keyword(s):

Ribonucleic Acid ◽

Deoxyribonucleic Acid ◽

In Vitro Transcription

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o,p′-DDT (1,1,1-trichloro-2 (p-chlorophenyl) 2-(o-chlorophenyl) ethane is a purely estrogenic agonist in the rat uterus in vivo and in vitro

Biochemical Pharmacology ◽

10.1016/0006-2952(87)90302-9 ◽

1987 ◽

Vol 36 (3) ◽

pp. 397-400 ◽

Cited By ~ 19

Author(s):

Paul Galand ◽

Nicole Mairesse ◽

Chantal Degraef ◽

Jacques Rooryck

Keyword(s):

Rat Uterus

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METABOLISM OF 20β-HYDROXY-4-PREGNEN-3-ONE IN UTERINE TISSUE OF NON-PREGNANT RATS IN VITRO

Acta Endocrinologica ◽

10.1530/acta.0.0830604 ◽

1976 ◽

Vol 83 (3) ◽

pp. 604-620 ◽

Cited By ~ 3

Author(s):

B. P. Lisboa ◽

M. Holtermann

Keyword(s):

Biological Activity ◽

Adult Female ◽

Female Rats ◽

Uterine Tissue ◽

Rat Uterus ◽

Adult Rats ◽

Pregnant Rats ◽

Progesterone Metabolites ◽

Ovariectomized Adult Rats

ABSTRACT In vitro experiments carried out with uterus preparations of ovariectomized adult rats indicate the presence in this tissue of a 20β-hydroxysteroid-oxidoreductase which catalyzes the conversion of 20β-hydroxy-4-pregnen-3-one to progesterone. Since a hepatic 20β-hydroxysteroid-oxidoreductase is absent in adult female rats, the myometrial enzyme can be responsible for the biological activity of 20β-hydroxy-4-pregnen-3-one in these animals. Besides progesterone five metabolites were isolated and identified after incubation of [4-14C]20β-hydroxy-4-pregnen-3-one with uterine tissue: 20β-hydroxy-5α-pregnan-3-one, 20β-hydroxy-5β-pregnan-3-one, 5α-pregnane-3α,20β-diol, 4-pregnene-3α,20β-diol and 4-pregnene-3β,20β-diol. The conversion of 20β-hydroxy-4-pregnen-3-one to progesterone permits us to regard all five steroids isolated as progesterone metabolites in the rat uterus. 20β-hydroxy-5β-pregnan-3-one is the first C21-metabolite with a 5β(H)-configuration isolated in the rat uterus, which indicates the presence of 5β-reductase in this tissue.

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