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At least 19 recordsLinked to original sources
PubMed1975

Steroidal anaesthetics: synthesis of 3alpha-hydroxy-5alpha-pregnane-11,20-dione-(21-14C) and 3alpha,21-dihydroxy-5alpha-pregnane-11,20-dione-(21-14C) 21-acetate.

3alpha-Hydroxy-5alpha-pregnane-11,20-dione-[21-14C] and 3alpha,21-dihydroxy-5alpha-pregnane-11,20-dione-[21-14C] 21-acetate were prepared from a common radio-labelled intermediate, 21-diazo-3alpha-hydroxy-5alpha-pregnane-11,20-dione-[21-14C] 3-nitrate, obtained by the reaction of 17beta-chlorocarbonyl-3alpha-hydroxy-5alpha-androstan-11-one 3-nitrate with diazomethane-[14C].

Alfaxalone Alfadolone Mixture↗
PubMed1978

Urinary excretion of 5beta-pregnane-3alpha,20alpha,21-triol in human gestation.

The steroids in urine from normal pregnant women have been studied. After extraction of conjugate steroids, solvolysis and enzymatic hydrolysis, the liberated steroids were separated by chromatography on Sephadex LH-20, and were analysed by gas-liquid chromatography and gas chromatography mass spectrometry. The following steroids were isolated and completely identified in the LH-20 fraction 7: 5beta-pregnane-3alpha,20alpha-diol, 5beta-pregnane-3alpha,17,20alpha-triol, 5beta-pregnane-3alpha,20alpha,21-triol and 5alpha-pregnane-3beta,16alpha,20alpha-triol. In addition, two metabolites tentatively identified as 5xi-pregnane-2xi,3xi,20xi-triol and 2xi,3xi,16xi-trihydroxy-5xi-pregnan-20-one, have not been reported as occcurring in urine from pregnant women. The 5beta-pregnane-3alpha,20alpha,21-triol was detected only in the third trimester of pregnancy and the urinary excretion values are between 320 and 650 microgram per 24 h. With the present data, it is not possible to establish the precursor(s) of this steroid. However, these results tentatively suggest that 5beta-pregnane-3alpha,20alpha,21-triol arises from foeto-placental unit.

Chromatography, Gas↗
PubMed1976

Isolation, identification and quantitation of serum 5alpha-pregnane-3,20-dione and its relationship to progesterone in the pregnant mare.

5alpha-pregnane-3,20-dione was isolated from pooled pregnant mare serum using Sephadex LH-20 column chromatography and identified by the use of radioimmunoassay, gas-liquid chromatography and gas-liquid chromatography-mass spectrometry analyses. 5beta-pregnane-3,20-dione was not cross-reactive with the radioimmunoassay system and was not detected by gas-liquid chromatography. Peripheral blood levels of progesterone and 5alphs-pregnane-3,20-dione were determined by radioimmunoassay in four Quarter Horse mares for the first 150 days of gestation. Progesterone and 5alpha-pregnane-3,20-dione declined from a range of 6 to 15 ng/ml at day 10 to a range of 2 to 8 ng/ml at day 40. After day 40 there was an increase in progesterone and 5alpha-pregnane-3,20-dione concentration. Toward the end of 150 days of gestation progesterone tended to decline; whereas, 5alpha-pregnane-3,20-dione levels were maintained or increased to levels as high as 35 ng/ml. Neither source nor function of 5alpha-pregnane-3,20-dione is known.

Animals↗
PubMed1976

Identification of two 5alpha-reduced pregnanes as major metabolites of progesterone in immature rat ovaries (1000 x g supernatant) in vitro.

Incubation of the 1000 x g supernatant obtained from 23-day-old rat ovarian homogenate with labeled progesterone resulted in the production of 3 major metabolites; 5alpha-androstane-3alpha,17beta-diol, and two 5alpha-reduced pregnanes that were identified as 3alpha-hydroxy-5alpha-pregnan-20-one and 3alpha,17alpha-dihydroxy-5alpha-pregnan-20-one. The 3alpha,17alpha-dihydroxy-5alpha-pregnan-20-one has not been hitherto isolated from mammalian ovaries. The steroids were identified by their mobilities on thin-layer and gas-liquid chromatography, by mass spectroscopy, derivative formation and by recrystallization to constant specific activity. In another experiment, incubation of the 1000 x g supernatant from 23-day-old rat ovaries with 3alpha-hydroxy-5alpha-pregnan-20-one as substrate resulted in the production of 5alpha-androstane-3alpha,17beta-diol. It is suggested that 5alpha-androstane-3alpha,17beta-diol is produced in immature rat ovaries by a pathway in which the identified 5alpha-reduced pregnanes serve as intermediates.

Androstane-3,17-diol↗
PubMed1977

Progesterone and 5alpha-pregnane-3,20-dione in peripheral blood of normal young women: Daily measurements throughout the menstrual cycle.

The peripheral plasma concentrations of progesterone and 5alpha-pregnane-3,20-dione were measured daily throughout the ovarian cycle of five presumptively ovulatory women. The concentrations of progesterone and 5alpha-pregnane-3,20-dione during the follicular phase were 0.11 +/- 0.02 ng/ml (mean +/- SE) and 0.16 +/- 0.01 ng/ml, respectively. In four of these women the concentrations of both progesterone and 5alpha-pregnane-3,20-dione began to rise immediately after the luteinizing hormone (LH) peak and reached maximal concentrations five to eight days later (progesterone: 8.6 to 19.9 ng/ml; 5alpha-pregnane-3,20-dione: 1.4 to 2.8 ng/ml). The luteal phases in these women, measured from the day of the LH peak to the onset of the next menses, varied from 13 to 18 days. In the other woman with a late LH surge (day 27 of the cycle) the peak concentrations of progesterone and 5alpha-pregnane-3,20-dione were reached four days after the LH peak (8.9 ng/ml and 0.8 ng/ml, respectively). The luteal phase in this woman was 11 days. From the results of this study, it appears that the concentrations of 5alpha-pregnane-3,20-dione in peripheral blood during the luteal phase are proportional to the availability of progesterone as substrate for the 5alpha-reductase enzyme system.

Female↗
PubMed1979

The source of the 5-alpha-pregnanes that occur during gestation in mares.

[1,2,6,7-3H]Progesterone was injected into the uterine artery of umbilical vein of 4 pregnant Ponies to determine whether 5 alpha-pregnane-3,20-dione (DHP), 20 alpha-hydroxy-5 alpha-pregnan-3-one (20 alpha-ol), and 3 beta-hydroxy-5 alpha-pregnan-20-one (3 beta-ol) are produced by the placenta, fetus, or mare during late gestation. Plasma samples were collected from indwelling catheters in the uterine artery and vein and the umbilical artery and vein at frequent intervals until 6 h after isotope injection. The plasma samples were extracted with organic solvents and the respective pregnanes were isolated by thin-layer chromatography. Mean plasma levels of radioactive DHP in the umbilical vein were greater (P less than 0.05) than those in the umbilical artery but were similar to those in the uterine artery and vein. Plasma levels of radioactive 20 alpha-ol in the umbilical artery and vein were less (P less than 0.05) than those in the uterine artery but similar to those in the uterine vein. Levels of radioactive 3 beta-ol in the umbilical artery were greater (P less than 0.05) than those in uterine artery and vein and similar to those in the umbilical vein. We suggest that DHP was produced by the placenta and a maternal source, that 20 alpha-ol was primarily of maternal origin, and that 3 beta-ol was formed primarily by the fetus.

Animals↗
PubMed1975

Isolation and characterization of 5alpha-pregnane-3,20-dione and progesterone in pepipheral blood of pregnant women. measurement throughout pregnancy.

5alpha-Pregnane-3,20-dione and progesterone were isolated from a pregnancy plasma pool and were identified by using a combination of chromatographic techniques and mass spectrometry. Antibodies to progesterone were obtained in rabbits by immunization with progesterone-1alpha-carboxyethyl-thioether-thyroglobulin. The raised antibodies were of high affinity and one of them cross-reacted (137%) with 5alpha-pregnane-3,20-dione. This property was used to develop radioimmunoassays for measuring circulating levels of both progesterone and 5alpha-pregnane-3,20-dione in pregnancy plasma. The levels of both progesterone and 5alpha-pregnane-3,20-dione increase throughout pregnancy, but a highly significant increase is observed only after the 32nd week of gestation.

Animals↗
PubMed1976

Trimethylsilyl group migration during electron impact and chemical ionization mass spectrometry of the trimethylsilyl ethers of 20-hydroxy-5alpha-pregnan-3-ones and 20-hydroxy-4-pregnen-3-ones.

The electron impact and chemical ionization (isobutane) mass spectra of the TMS derivatives of 20-hydroxy-5alpha-pregnan-3-ones and 20-hydroxy-4-pregnen-3-ones include ions [M--44]+-attributable to loss of a CH3CHO fragment from C-17 with migration of the TMS group to the charge-retaining fragment. Mass spectra of isotopically labelled ([3-18O], [20-18O] and [2H9-TMS]) analogues are consistent with this mechanism; [2H9-TMS] labelling further indicates that subsequent loss of a methyl group from [M--44]+-ions does not involve the TMS group. Corresponding ions are not observed at significant abundance in the spectra of 20beta-trimethylsilyloxy-5alpha-pregnane and 20beta-trimethylsilyloxy-4-pregnen-3-one 3-O-methyloxime. In the electron impact mass spectrum of the t-butyldimethylsilyl ether of 20beta-hydroxy-4-pregnen-3-one, an ion is observed corresponding to loss of 44 atomic mass units from the intense [M--C4H9]+ ion.

Electrochemistry↗
PubMed1975

Conversion of progesterone-1,2-3-H to 5beta-pregnane-3,20-dione by brain tissue.

The presence of a 5beta-reductase acting to convert progesterone to 5beta-pregnane-3,20-dione is described in the soluble 105,000 x g fraction of a preparation of dog cerebral cortex. The function of this enzymatic activity is obscure but may be important in regulation of sensorium. 5beta-pregnane compounds are potent depressors of the central nervous system.

Animals↗
PubMed1979

18-substituted steroids. Part 4. A chemical synthesis of 3 alpha,18,21-trihydroxy-5 beta-pregnan-20-one 18--20-hemiacetal (18-hydroxy-tetrahydro-DOC).

3 alpha,18,21-Trihydroxy-5 beta-pregnan-20-one 18 leads to 20-hemiacetal (18-hydroxy-tetrahydro-DOC) has been prepared from 3 alpha-acetoxy-5 beta-pregnan-20-one by reduction to the 20 beta-alcohol, application of the 'hypoiodite' reaction [Pb(OAc)4-I2-hv] with subsequent steps leading to the 18-hydroxy-20-ketone (as hemiacetal), and C-21 acetoxylation [Pb(OAc)4] followed by hydrolysis.

18-Hydroxydesoxycorticosterone↗
PubMed1979

Metabolism of progesterone in the pregnant sheep near term: identification of 3 beta-hydroxy-5 alpha-pregnan-20-one 3-sulfate as a major metabolite.

Two pregnant ewes near term were given a single injection of progesterone-4-14C via the left jugular vein, and serial blood samples were taken from the right jugular vein at 5 min intervals over a period of 40 min. Radioactive steroids in the plasma were separated into unconjugated and conjugated fractions which were further isolated and analysed by established methods. The injected hormone was rapidly metabolized with a half-life of approximately 10 min and metabolic clearance rate about 3.5 liters min. The bulk of the metabolites was found in the sulfate fraction from which a major metabolite was identified as 3 beta-hydroxy-5 alpha-pregnan-20-one. From the unconjugated fraction, 20 alpha-hydroxy-pregn-4-en-3-one, a known minor metabolite was also isolated. No radioactive estrogens were found. It is concluded that a major portion of circulating progesterone in the pregnant ewe near term is cleared by 5 alpha-reduction of ring A, followed by sulfo-conjugation.

Animals↗
PubMed1975

Gas-liquid chromatographic studies of reactions and structural relationships of steroids. II. Positions 3, 11, and 20 in the pregnane series.

Qualitative and quantitative effects of classical reactions on steroids observed by gas-liquid chromatography (GLC) under standardized conditions, including the double internal standard technique, are reported. Simple procedures applicable to nanogram amounts of reactants which afford excellent yields of the major products are described. Reactions studied include the Wolff-Kishner removal of keto groups (WK), their conversion to hydroxyl groups by NaBH4(RD), and to dioxolone derivatives by ethylene glycol (DO); the conversion of hydroxyl to keto groups by CrO3 (OX), and to TMS ethers by hexamethyldisilazane; the hydrolysis of dioxolone and TMS derivatives by H+ (HY). GLC chromatograms of reaction mixtures of single and multistep reactions readily provide information on effects on functional groups at positions 3, 11, and 20 in the pregnane series, and the retention times of many steroids unavailable from commercial or other sources. GLC data analysis provides relationships between steroid structure and retention time from which methods for the computation of retention times and for steroid identification are designed. The accuracy of the computation methods is demonstrated.

Chemical Phenomena↗
PubMed1975

Gas-liquid chromatographic studies of reactions and structural relationships of steroids. IV. Substitution in the pregnane side-chain.

Qualitative and quantitative effects of classical reactions on steroids observed by gas-liquid chromatography (GLC) under standardized conditions, including the double internal standard technique are reported. Simple procedures applicable to nanogram amounts of reactants are described. Reactions studied include the conversion of keto groups to hydroxyl groups by NaBH4, and to dioxolone derivatives by 1,2-diethanol; 17 alpha-hydroxylation of C20-ketosteroids; the conversion of hydroxyl groups to trimethylsilyl (TMS) ethers by hexamethyldisilazane; the hydrolysis of dioxolone and TMS derivatives by H+. Effects of Wolff-Kishner reagents, and CrO3 were also studied. GLC chromatograms of reaction mixtures of single- and multistep reactions readily provide information on effects on functional groups at positions 3, 17, 20, and 21 in the pregnane series, and the retention times of many steroids unavailable from commercial and other sources. GLC data analysis provides relationships between steroid structure and retention time from which methods for the computation of retention times and for steroid identification are designed. The accuracy of the computation methods is demonstrated.

Chemical Phenomena↗
PubMed1977

Gas-liquid chromatographic studies of reactions and structural relationships of steroids. V. Concurrent substitution in the pregnane side-chain and position II.

Qualitative and quantitative effects of classical reactions on steroids observed by gas-liquid chromatography (GLC) under standardized conditions, including the double internal standard technique, are reported. Simple procedures applicable to nanogram amounts of reactants are described. Reactions studied include the conversion of keto groups to hydroxyl groups by NaBH4, and the removal of the pregnane side-chain with NaBiO3. GLC chromatograms readily provide information on effects on functional groups at positions 3, 11, 17, 20, and 21 and the retention times of many steroids unavailable from commercial sources. GLC data analysis provides relationships between steroid structure and retention time from which methods for the computation of retention times and steroid identification are designed. The accuracy of these methods is demonstrated.

Chemical Phenomena↗
PubMed1975

Gas-liquid chromatographic studies of reactions and structural relationships of steroids. Part III. 11alpha-hydroxysteroids of the androstane and pregnane series.

Qualitative and quantitative effects of classical reactions on steroids observed by gas-liquid chromatography (GLC) under standardized conditions, including the double internal-standard technique, are reported. Simple procedures applicable to nanogram amounts of reactants which afford excellent yields of the major products are described. Reactions studied include the Wolff-Kishner removal of keto groups, their conversion into hydroxyl groups with sodium-ethanol or sodium borohydride and into dioxolone derivatives with ethylene glycol; the conversion of hydroxyl into keto groups with chromium trioxide and to trimethylsilyl (TMS) ethers by hexamethyldisilazane; the hydrolysis of dioxolone and TMS derivatives by H+. Gas-liquid chromatograms of reaction mixtures of single- and multistep reactions readily provide information on the effects on the 11alpha-hydroxy and other functional groups at positions 3 and 17 (androstane series) and positions 3 and 20 (pregnane series), and the retention times of many steroids unavailable from commercial or other sources. GLC data analysis provides relationships between steroid structure and retention time from which methods for the computation of retention times and for steroid identification are designed. The accuracy of the calculation methods is demonstrated.

11-Hydroxycorticosteroids↗
PubMed1976

Endogenous concentration of progesterone and 2 slpha -pregnane-3,20-dione in rat decidula tissue.

The endogenous concentration of progesterone (P) and 5 alpha-pregnane-3,20-dione (5AP) were determined in the dedicual tissue of mature rats by radiommunoassay. On the 4th day of pseudopregnancy the uterine concentration was 281 +/- 28 ng/g for P and 266 +/- 41 ng/g for 5AP. Horns were traumatized on the 4th day of pseudopregnancy. On the 4th day following trauma the endometrial concentration of P was 100 +/- 7 ng/g and for 5AP was 104 +/- 10 ng/g. Plasma concentrations were 35.5 +/- 4.1 ng/g. For P and 16.1 +/- 4.9 ng/ml for 5AP. When one horn was removed and the contralateral horn was traumatized, there was direct correlation between the endogenous concentrations of P and 5AP in the previously removed utraumatized horn and the amount of decidual tissue in the contralateral horn 4 days following trauma (r2 = .8949). These experiments indicate the endometrial response to progesterone is a complex process determined in part by local metabolsm and the ability of the uterus to concentrate P.

Animals↗
PubMed1975

Significance of 3alpha, 17 alpha-dihydroxy-5beta-pregnane-20-one in the diagnosis of congenital adrenal hyperplasia.

The 3alpha-17alpha-dihydroxy-5beta-pregnane-20-one (17-hydroxy-pregnanolone) excretion was found by gas chromatography to be as high as the pregnanetriol in urine of 4 virilising CAH female and 2 male patients. According to our results the significance of the determination of 17-hydroxy-pregnanolone is equal to that of the pregnanetriol in the diagnosis of adrenal hyperplasia. As the 17-hydroxy-pregnanolone is demonstrable after mild acid hydrolysis, too, it can be applied independently from the pregnanetriol determination. In five out of the six patients we found the excretion of the pregnanediol to be high, too. Its value reached, irrespective of sex, the characteristic quantity of the woman's luteal phase, so it undoubtedly originated from the adrenal cortex. We dealt shortly with the explanation of high pregnanediol excretion.

17-alpha-Hydroxypregnenolone↗