THE CONVERSION OF DEHYDROEPIANDROSTERONE-7α-3H TO OESTROGENS BY CORPORA LUTEA OF EARLY HUMAN PREGNANCY

1967 ◽  
Vol 54 (1) ◽  
pp. 30-36 ◽  
Author(s):  
George L. Flickinger ◽  
Chung-Hsiu Wu ◽  
Joseph C. Touchstone
Keyword(s):  
Thin Layer ◽  
Early Pregnancy ◽  
Specific Activity ◽  
Corpora Lutea ◽  
Slice Preparation ◽  
Human Pregnancy ◽  
Specific Activities ◽  
Layer Chromatography ◽  
Early Human ◽  
Human Corpus Luteum

ABSTRACT Incubation of two corpora lutea of early human pregnancy in the presence of dehydroepiandrosterone-7α-3H resulted in a 33—44% yield of oestrone plus 17β-oestradiol. The major oestrogen formed in homogenate preparations was oestrone while in a slice preparation it was 17β-oestradiol. Oestrone and 17β-oestradiol were characterized by solvent partition, paper chromatography and crystallization to constant specific activity after addition of carrier. Acetates of the crystallized oestrogens had the same specific activities as the parent steroids and these derivatives were further identified by thin layer chromatography. These results suggest that dehydroepiandrosterone may serve as a major precursor for oestrogen biosynthesis by human corpus luteum of early pregnancy.

THE LESS-POLAR METABOLITES PRODUCED BY INCUBATION OF TESTOSTERONE-4-14C WITH RAT AND BOVINE BRAIN

1969 ◽  
Vol 61 (4) ◽  
pp. 641-648 ◽  
Author(s):  
Leon J. Sholiton ◽  
Emile E. Werk
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Paper Chromatography ◽  
Specific Activity ◽  
Bovine Brain ◽  
Polar Fraction ◽  
End Products ◽  
Polar Metabolites ◽  
Layer Chromatography ◽  
Constant Specific Activity

ABSTRACT Rat and bovine brain have been incubated with testosterone-4-14C under standard conditions. With use of paper chromatography, the extracted metabolites were noted to fall into less-polar, iso-polar, and more polar fractions. The components of the less-polar fraction were separated by acetylation and thin-layer chromatography and the major end-products identified by recrystallization to constant specific activity or constant 3H/14C ratios. Androst-4-enedione and 5α-dihydrotestosterone were formed consistently under the conditions utilized. Trace amounts of other less-polar metabolites were noted occasionally.

THE ULTRASTRUCTURE OF THE HUMAN GRANULOSAL LUTEIN CELL OF THE FIRST TRIMESTER OF GESTATION

1968 ◽  
Vol 58 (3) ◽  
pp. 481-496 ◽  
Author(s):  
Poul Hjortkjær Pedersen ◽  
Jørgen Falck Larsen
Keyword(s):  
Endoplasmic Reticulum ◽  
Smooth Endoplasmic Reticulum ◽  
First Trimester ◽  
Corpora Lutea ◽  
Steroid Synthesis ◽  
Intracellular Location ◽  
Human Pregnancy ◽  
Subendothelial Space ◽  
Lutein Cell ◽  
Early Human

ABSTRACT The ultrastructure of granulosal lutein cells of 13 corpora lutea in early human pregnancy was studied. The predominant cytoplasmic element was the smooth endoplasmic reticulum. No convincing signs of degeneration of the lutein cells could be demonstrated within the first 14 weeks of pregnancy, as the mitochondria as well as the rough and smooth endoplasmic reticulum were well preserved. However, lysosomes may be slightly more numerous in older specimens and the subendothelial space increases with the age of gestation. A particular type of multilaminated structure one to five micron in diameter was observed, particularly in the earliest specimens. The possible intracellular location of steroid synthesis is discussed.

Mammary uptake and metabolism of progesterone in goats and its effect on milk progesterone concentrations during the oestrous cycle and early pregnancy

1983 ◽  
Vol 98 (2) ◽  
pp. 263-270 ◽  
Author(s):  
R. J. Holdsworth ◽  
R. B. Heap ◽  
J. Goode ◽  
M. Peaker ◽  
D. E. Walters
Keyword(s):  
Mammary Gland ◽  
Thin Layer ◽  
Early Pregnancy ◽  
Oestrous Cycle ◽  
Plasma Samples ◽  
Milk Samples ◽  
Layer Chromatography ◽  
Uptake And Metabolism ◽  
In Pregnancy ◽  
Venous Plasma

Following the observation that the concentration of progesterone in goats' milk differs appreciably according to the specificity of the antiserum used in a non-extraction (direct) radioimmunoassay, experiments were carried out to find an explanation for these results. Milk and plasma samples were collected during the oestrous cycle and during an equivalent period of pregnancy after a fertile mating. Samples were analysed by a direct radioimmunoassay using two antisera, 18/3 which is highly specific for progesterone and 465/6 which is less specific, and by radioimmunoassay of fractions isolated by thin-layer chromatography (TLC). Values obtained for milk and plasma samples collected during the oestrous cycle and early pregnancy were similar, except that values for milk samples measured with antiserum 465/6 were higher in pregnancy compared to those obtained during the oestrous cycle. Values obtained for milk and plasma with antiserum 465/6 were significantly higher than those obtained with 18/3 (P<0·001). After TLC this difference was found to be due principally to the presence of compound(s) with chromatographic properties identical to 5-pregnanedione(s). A comparison of the concentration measured in arterial and mammary venous plasma and in milk showed that about 25% of progesterone (5·7 nmol/min) was extracted by the mammary gland, and that substantial amounts of immunoreactive metabolites of progesterone are secreted into milk with only small quantities being transferred into mammary vein plasma.

CONVERSION OF DEHYDROEPIANDROSTERONE-7α-3H TO OESTROGENS BY CORPUS LUTEUM, PLACENTA, AND PLACENTA PLUS FOETAL VISCERA IN EARLY HUMAN PREGNANCY

1967 ◽  
Vol 54 (1) ◽  
pp. 181-188 ◽  
Author(s):  
Chung-Hsiu Wu ◽  
George L. Flickinger ◽  
Joseph C. Touchstone
Keyword(s):  
Corpus Luteum ◽  
Early Pregnancy ◽  
Human Pregnancy ◽  
Early Human

ABSTRACT A corpus luteum, placenta, and placenta plus foetal viscera of a 13-week old human pregnancy were incubated with dehydroepiandrosterone-7α-3H in vitro. Conversion to oestrone and 17β-oestradiol was found in all incubates. Oestriol was formed from dehydroepiandrosterone only in the incubate of placenta plus foetal viscera. Thus, in early pregnancy dehydroepiandrosterone may serve as a precursor for oestrogen biosynthesis not only in the foeto-placental compartment, but also in the corpus luteum.

CONVERSION OF ANDROST-4-ENE-3,17-DIONE-4-14C TO OESTROGENS BY SUBCELLULAR FRACTIONS OF THE HUMAN CORPUS LUTEUM OF THE NORMAL CYCLE

1967 ◽  
Vol 56 (2) ◽  
pp. 225-230 ◽  
Author(s):  
Rosalinda B. Arceo ◽  
Kenneth J. Ryan
Keyword(s):  
Subcellular Localization ◽  
Corpus Luteum ◽  
Paper Chromatography ◽  
Specific Activity ◽  
Subcellular Fractions ◽  
Corpora Lutea ◽  
Differential Centrifugation ◽  
Normal Cycle ◽  
Generating System ◽  
Human Corpus Luteum

ABSTRACT The subcellular localization of the aromatizing enzymes from four human corpora lutea was investigated. Subcellular fractions were prepared by differential centrifugation, and incubations of each fraction were carried out with androst-4-ene-3,17-dione-4-14C and a TPNH generating system. Oestrogen metabolites were characterized by phenolic separation, repeated paper chromatography, incubation with freshly prepared placental 17β-ol dehydrogenase, methylation and recrystallization to constant specific activity. The experimental results indicate that the aromatizing enzymes were localized mainly in the microsomal fractions of homogenates of human corpora lutea.

Eine Mikromethode zur Markierung von Steroiden und von Ecdyson mit Tritium

1963 ◽  
Vol 18 (3) ◽  
pp. 219-224 ◽  
Author(s):  
Peter Karlson ◽  
Rainer Maurer ◽  
Martin Wenzel
Keyword(s):  
Thin Layer ◽  
Room Temperature ◽  
Special Flow ◽  
Activity Measurements ◽  
Pure Substances ◽  
Model Substances ◽  
Specific Activities ◽  
High Doses ◽  
Layer Chromatography ◽  
By Products

For labelling of the metamorphosis hormone, ecdysone, with tritium, a modified Wilzbach technique has been worked out. Polyhydroxysteroids (Δ1-5α-Pregnendiol-(17α,21)-trion(3,11.20)-21-acetate and 5α-Pregnandiol-(17α,21)-trion(3,11,20)-21-acetate) were used as model substances. The best yields and highest activities were obtained by adsorbing the substances on granulated and activated charcoal, enclosing the absorbates in Nylon bags and exposing them to high doses of tritium at room temperature. The adsorption resulted also in a decrease of radioactive by-products. The tritiated substances were purified by thin-layer chromatography, using a special flow-counter for activity measurements on the chromatoplates. The method described is especially valuable with small amounts (5 - 20 mg). Specific activities up to 250 μC/mg of the pure substances have been obtained.

Movement and Activity of Glyphosate in Purple Nutsedge

Weed Science ◽  
1977 ◽  
Vol 25 (3) ◽  
pp. 268-274 ◽  
Author(s):  
Bernard H. Zandstra ◽  
Roy K. Nishimoto
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Specific Activity ◽  
Cyperus Rotundus ◽  
Plant Age ◽  
Purple Nutsedge ◽  
Plant Parts ◽  
Layer Chromatography ◽  
Application Specific

Tubers from purple nutsedge (Cyperus rotundusL.) plants grown in the greenhouse for 2 to 10 weeks did not germinate after foliar applications of 4 kg/ha glyphosate (N-(phosphonomethyl)glycine). Some tubers from 12- and 24-week-old purple nutsedge plants survived glyphosate application. Translocation of14C-glyphosate from treated purple nutsedge leaves to other plant parts increased from 5% of the amount applied at 1 day to 19% at 4 days after application. Specific activity of14C in tubers was greater than in leaves of plants 2- to 6-week-old. With increasing plant age, specific activity decreased in both tubers and leaves. As purple nutsedge grew older, total14C translocated increased in tubers, and decreased slightly in leaves. Thin layer chromatography showed no evidence of glyphosate metabolism in purple nutsedge.

Determination of specific activity of isotopic materials by thin layer chromatography

Lipids ◽  
1972 ◽  
Vol 7 (6) ◽  
pp. 420-425 ◽  
Author(s):  
Wil Wortmann ◽  
Maria Kasparow ◽  
Joseph C. Touchstone
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Specific Activity ◽  
Layer Chromatography

Methionin als Methylgruppendonator für Zimtsäuren und Anthocyane

1964 ◽  
Vol 19 (2) ◽  
pp. 148-150 ◽  
Author(s):  
Dieter Hess
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Specific Activity ◽  
Methyl Groups ◽  
Cinnamic Acids ◽  
Flower Buds ◽  
Methyl Group ◽  
Red Cabbage ◽  
Hydroiodic Acid ◽  
Layer Chromatography

Seedlings of wheat, oat and red cabbage and flower buds of petunia were supplied with ʟ-methionine (methyl-14C). Cinnamic acids and anthocyanins were purified by thin layer chromatography to constant specific activity. The methylated compounds had an 16-30 fold higher activity than the non-methylated ones. By splitting with hydroiodic acid it was shown that the methyl groups of cinnamic acids and anthocyanins contained radioactivity. Therefore the O-methylgroups of both cinnamic acids and anthocyanins had arisen from the methyl group of methionine.

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