scholarly journals Incorporation of [3H] uridine into the ribonucleic acid of rat uterus during pseudopregnancy and in the presence of I.C.I. 46474 [trans-1-(p-β-dimethylaminoethoxyphenyl)-1,2-diphenylbut-1 -ene]

1970 ◽  
Vol 119 (4) ◽  
pp. 609-613 ◽  
Author(s):  
J. E. O'Grady ◽  
P. J. Heald ◽  
Anne O'Hare
Keyword(s):  
Ribonucleic Acid ◽  
Untreated Control ◽  
Rna Synthesis ◽  
Uterine Tissue ◽  
Rat Uterus ◽  
Pregnant Rat ◽  
Uridine Incorporation ◽  
Important Requirement ◽  
Dose Concentration ◽  
Different Doses

1. The incorporation of [3H]uridine into RNA of rat uterine tissue has been measured during pseudopregnancy and in rats receiving different doses of an anti-implantation compound [trans-1-(p-β-dimethylaminoethoxyphenyl)-1,2-diphenylbut- 1-ene, I.C.I. 46474]. 2. In the uterus of the pseudopregnant rat uridine incorporation into RNA increased markedly on day 3 of pseudopregnancy, remained high until day 5 and decreased sharply by day 6, rising again by day 9. 3. This pattern of change was similar to, but not identical with, that previously found in the pregnant rat. 4. Rats receiving I.C.I. 46474 at a dose concentration below that preventing implantation showed a pattern of RNA synthesis similar to that found in untreated control rats. 5. Rats treated with doses of I.C.I. 46474 sufficient to inhibit implantation revealed a totally different pattern of incorporation of [3H]uridine into uterine RNA. 6. The results are discussed in terms of previous findings with the normally pregnant rat. It is concluded that the increasing uterine RNA synthesis found on day 3 in the pregnant rat is an important requirement for the occurrence of the subsequent implantation.

scholarly journals The uptake of [3H]uridine into the nucleic acids of rat uterus during early pregnancy

1970 ◽  
Vol 117 (1) ◽  
pp. 65-71 ◽  
Author(s):  
P. J. Heald ◽  
J. E. O'grady
Keyword(s):  
Nucleic Acids ◽  
Dna Content ◽  
Dry Matter ◽  
Rna Synthesis ◽  
Early Stage ◽  
Uterine Tissue ◽  
Rat Uterus ◽  
Independent Analysis ◽  
Implantation Sites ◽  
Rna And Dna

1. Changes in content and uptake of [3H]uridine into the nucleic acids of rat uterus during the first 9 days of pregnancy were studied. 2. From day 6 implantation sites were separated from the rest of the uterine tissue for independent analysis. 3. Up to day 5 of pregnancy no changes were found in the total dry matter or in RNA and DNA content/unit dry matter nor in the RNA/DNA ratios. 4. From day 6, when implantation sites are visible, the water content of the implantation sites increased by 2–3%, and the RNA content/unit dry wt. and the RNA/DNA ratios increased. The DNA content/unit dry wt. did not increase in the implantation sites until day 8. 5. Uptake of [3H]uridine into the acid-soluble fraction of the tissues was markedly higher in implantation sites than in non-implantation sites. 6. Uptake of [3H]uridine into RNA was significantly increased on day 3 of pregnancy and again on day 5. 7. On days 6 and 7, the incorporation into RNA of implantation sites was significantly higher than in the remainder of the uterine tissue but decreased on days 8 and 9 to the same value as that of the normal tissue. 8. No change occurred in uptake into DNA until day 6, when there was an increase in uptake by the implantation sites. 9. It is suggested that the increase in RNA synthesis on day 3 is a preparation of the uterus for the onset of implantation on day 5, and that increased synthesis in implantation sites on days 6 and 7 is the elaboration of new RNA necessary for this early stage of pregnancy to commence.

PROGESTERONE IN THE UTERUS

1974 ◽  
Vol 77 (1) ◽  
pp. 160-170 ◽  
Author(s):  
D. Egert ◽  
H. Maass
Keyword(s):  
Extracellular Fluid ◽  
Uterine Tissue ◽  
Rat Uterus ◽  
Pregnant Rats ◽  
Pregnant Rat

ABSTRACT Radio-metabolites of progesterone and progesterone itself were found in the uteri of intact pregnant rats 20 min after injection of [1,2-3H]progesterone. However, after evisceration and removal of the foeto-placental unit, and following injection of the labelled steroid, the progesterone content in the extract from the pregnant rat uterus markedly increased while the metabolite levels correspondingly decreased. An analogous change was observed in the plasma. Thus it appears probable that progesterone is not metabolized in the uterus of pregnant rats, and that metabolites found in this tissue originate predominantly in the foetoplacental system and appear in the plasma and extracellular fluid present in the uterine tissue.

scholarly journals Ribonucleic Acid Biosynthesis in Human Leukocytes

Blood ◽  
1966 ◽  
Vol 28 (2) ◽  
pp. 188-200 ◽  
Author(s):  
MARTIN J. CLINE
Keyword(s):  
Density Gradient ◽  
Ribonucleic Acid ◽  
Turnover Rate ◽  
Rna Synthesis ◽  
Gradient Analysis ◽  
Sucrose Density Gradient ◽  
Acid Biosynthesis ◽  
Total Load ◽  
Human Leukocytes ◽  
Particle Ingestion

Abstract Phagocytosis has profound effects on several aspects of the RNA metabolism of human leukocytes. The major changes induced by particle ingestion appear to be (1) an increased uptake of pyrimidine precursors from the suspending medium, (2) a contraction in the size of the nucleotide pool, (3) an accelerated rate of destruction of preexisting RNA, and (4) an increased rate of RNA synthesis. Sucrose density gradient analysis of the newly synthesized RNA suggests that several classes of RNA are involved in this process. The increased turnover rate of the nucleotide pool and of the cellular RNA of the leukocyte is proportional, within limits, to the total load of ingested particles.

Hormone-induced differentiation of antheridial branches in Achlya ambisexualis: dependence on ribonucleic acid synthesis

1974 ◽  
Vol 20 (7) ◽  
pp. 977-980 ◽  
Author(s):  
David K. Horowitz ◽  
Peter J. Russell
Keyword(s):  
Sexual Differentiation ◽  
Ribonucleic Acid ◽  
Rna Synthesis ◽  
Actinomycin D ◽  
Steroid Hormone ◽  
Acid Synthesis ◽  
Aquatic Fungus ◽  
Induced Differentiation ◽  
Sexual Steroid ◽  
Achlya Ambisexualis

Sexual differentiation in male strains of the aquatic fungus Achlya ambisexualis Raper is induced by antheridiol, a sexual steroid hormone secreted by female strains. Antheridiol-induced initiation of the morphologically distinct antheridial branches in male Achlya is completely prevented when DNA-dependent RNA synthesis is inhibited by actinomycin D. In addition antheridial branch elongation is inhibited to a degree proportional to the concentration of actinomycin D added. Thus, evidence indicates that RNA synthesis is required for antheridiol-induced initiation of antheridial branching and that continued RNA synthesis is required for elongation of antheridial branches.

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

1976 ◽  
Vol 83 (3) ◽  
pp. 604-620 ◽  
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.

scholarly journals Identification of myoelectric signals of pregnant rat uterus: new method to detect myometrial contraction

2017 ◽  
Vol 58 (2) ◽  
pp. 141-148 ◽  
Author(s):  
Kálmán F. Szűcs ◽  
György Grosz ◽  
Miklós Süle ◽  
Anikó Nagy ◽  
Zita Tiszai ◽  
...  
Keyword(s):  
New Method ◽  
Rat Uterus ◽  
Myoelectric Signals ◽  
Pregnant Rat

METABOLISM OF LEPTOSPIRES: II. THE ACTION OF 8-AZAGUANINE

1967 ◽  
Vol 13 (12) ◽  
pp. 1621-1629 ◽  
Author(s):  
Russell C. Johnson ◽  
Palmer Rogers
Keyword(s):  
Nucleic Acids ◽  
Ribonucleic Acid ◽  
Rna Synthesis ◽  
Inhibitory Effect ◽  
Relative Increase ◽  
Purine Biosynthesis ◽  
Low Concentrations

Both the pathogen Leptospira pomona and the saprophyte L. biflexa Patoc I can convert exogenous adenine, guanine, and 8-azaguanine to the corresponding nucleotide and incorporate them into nucleic acids. L. pomona is inhibited by low concentrations of 8-azaguanine (50 μg/ml) and this inhibition is associated with less than a 5% replacement of the ribonucleic acid (RNA) guanine residues by the analogue. Guanine possessed the highest activity for antagonizing the inhibitory effect of 8-azaguanine. The biosynthetic process of L. pomona most affected by the analogue was a relative increase in RNA synthesis. The analogue-resistant L. biflexa incorporated 1/10 as much 8-azaguanine as L. pomona. The higher rate of purine biosynthesis, in addition to the lesser amount of 8-azaguanine incorporated, may account for the analogue resistance of L. biflexa.

Sign in / Sign up

Export Citation Format

Share Document