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1.
The following steroids have been identified by combined gas chromatography-mass spectrometry in a urine specimen collected from a newborn chimpanzee; 5-androstene-3β, 17α-diol, 3β,16α (and 16β)-dihydroxy-5-androsten-17-one, 5-androstene-3β, 16α, 17β-triol, 5-androstene-3β, 16β, 17α-triol, 5-pregnene-3β, 20α-diol, 5-pregnene-3β, 20α, 21-triol, 3β,21-dihydroxy-5-pregnen-20-one, 3β, 16α-dihydroxy-5-pregnen-20-one, 5-Piegnene-3β, 16α,20α, 21-tetrol, 5-pregnene-3β,17α, 20ξ, 21-tetrol androstenetriolones and androstenetetrols.  相似文献   

2.
[4 -14C]-Progesterone was applied to the leaves of growing pea plants, Pisum sativum. After 3 weeks, about 50% of the administered steroid was reduced, about 20% being reduced to 5α-pregnane-3α,20β-diol as the major metabolite. The radioactivities of 5α-pregnane-3α,20α-diol and 5α-pregnane-3α,20β-diol after 3 weeks were more than twice those after one week. The following radioactive metabolises were also isolated: 5α-pregnane-3,20-dione; 20α-hydroxy-4- pregnen-3-one; 20β-hydroxy-4-pregnen-3-one; 3α-hydroxy-5α-pregnan-20-one; 3α-hydroxy-5β-pregnan-20-one; 3β-hydroxy- 5α-pregnan-20-one; 20β-hydroxy-5α-pregnan-3-one; 5α-pregnane-3β,20β-diol; and 5β-pregnane-3α,20β-diol. The radioactivities of the 5α-pregnane derivatives were considerably higher than those of the corresponding 5β-pregnane derivatives.  相似文献   

3.
The influence of androgens on the FSH modulation of progestin biosynthetic enzymes was studied in vitro. Granulosa cells obtained from immature, hypophysectomized, estrogen-treated rats were cultured for 3 days in a serum-free medium containing FSH (20 ng/ml) with or without increasing concentrations (10?9?10?6 M) of 17β-hydroxy-5α-androstan-3-one (dihydrotestosterone; DHT), 5α-androstane-3α, 17β-diol (3α-diol), or the synthetic androgen 17β-hydroxy-17-methyl-4,9,11-estratrien-3-one (methyltrienolone; R1881). FSH treatment increased progesterone and 20α-hydroxy-4-pregnen-3-one(20α-OH-P) production by 10.2- and 11-fold, respectively. Concurrent androgen treatment augmented FSH-stimulated progesterone and 20α-OH-P production in a dose-related manner (R1881 > 3α-diol > DHT). In the presence of an inhibitor of 3β-hydroxysteroid dehydrogenase (3β-HSD), the FSH-stimulated pregnenolone (3β-hydroxy-5-pregnen-20-one) production (a 20-fold increase) was further enhanced by co-treatment with R1881, 3α-diol or DHT. Furthermore, FSH treatment increased 4.4-fold the activity of 3β-HSD, which converts pregnenolone to progesterone. This stimulatory action of FSH was further augmented by concurrent androgen treatment. In contrast, androgen treatment did not affect FSH-stimulated activity of a progesterone breakdown enzyme, 20α-hydroxysteroid dehydrogenase(20α-HSD). These results demonstrate that the augmenting effect of androgens upon FSH-stimulated progesterone biosynthesis is not due to changes in the conversion of progesterone to 20α-OH-P, but involves an enhancing action upon 3β-HSDΔ5, Δ4-isomerase complexes and additional enzymes prior to pregnenolone biosynthesis.  相似文献   

4.
The crystal and molecular structure of (20R)-20-phenyl-5-pregnene-3β, 20-diol hemihydrate has been determined by X-ray analysis in order to establish the configuration and conformation at C(20). Interest in this compound was stimulated by its high affinity inhibitory binding to cytochrome P-450SCC, the enzyme which catalyzes the biosynthesis of pregnenolone(3β-hydroxy-5-pregnen-20-one) from cholesterol. The results of the analysis suggest a possible conformation for the cholesterol side chain in the enzyme complex.  相似文献   

5.
To characterize Leydig cell steroidogensis, we examined the metabolism of (3H)pregnenolone (3β-hydroxy-5-pregnen-20-one) to androgens in the presence and absence of human chorionic gonadotropin (hCG) as a function of culture duration. Approximately 20–30% of the (3H)pregnenolone was converted to testosterone (17β-hydroxy-4-androsten-3-one) by purified Leydig cells at 0, 3 and 5 days (d) of culture. Androstenedione (4-androstene-3,17-dione) and dihydrotestosterone (17β-hydroxy-5α-androstan-3-one) were also produced while on day 5 of culture, significant amounts of progesterone (4-pregnene-3, 20-dione) were isolated. The Δ5 intermediates, 17-hydroxypregnenolone (3β, 17-dihydroxy-5-pregnen-20-one) and dehydroepiandrosterone (3β-hydroxy-5-androsten-17-one), accounted for less than 1% of substrate conversion, indicating a clear preference for Leydig cells to metabolize (3H)pregnenolone via the Δ4 pathway. On day 0 of culture, unidentified metabolites consisted of predominately polar steroids while on day 5 of culture, the unidentified metabolites consisted of predominately nonpolar steroids. In the presence of hCG, (3H)pregnenolone metabolism did not differ from basal on day 0 or 3 of culture. HCG increased the conversion of pregnenolone to progesterone and 17-hydroxyprogesterone (17-hydroxy-4-pregnene-3, 20-dione) on 5d. This suggests that Leydig cells cultured for 5d have decreased C17–20 desmolase activity or that hCG acutely stimulates 3β-hydroxysteroid dehydrogenase and Δ45 isomerase activities.  相似文献   

6.
1. The possible involvement of 5-pregnene-3beta,20beta-diol in 16-unsaturated C(19) steroid biosynthesis has been investigated. 2. 5,16-Androstadien-3beta-ol (andien-beta) formation from [4-(14)C]pregnenolone (3beta-hydroxy-5-pregnen-20-one), 5-pregnene-3beta,20alpha-diol and 5-pregnene-3beta,20beta-diol was studied in homogenates of boar testis and the mean yields obtained were 25.6, 2.7 and 16.0% respectively. 3. Short-term kinetic studies with pregnenolone and 5-pregnene-3beta,20beta-diol separately and together suggested that the latter compound might be an intermediate in the biosynthesis of andien-beta. 4. In agreement with this interpretation, radioactive 5-pregnene-3beta,20beta-diol has been isolated during andien-beta biosynthesis from [4-(14)C]pregnenolone in the presence of NADPH, more radioactivity being trapped under limiting conditions of andien-beta formation with NADH present as cofactor. 5. Further, 5-pregnene-3beta,20beta-diol and andien-beta have been shown to inhibit the formation of the 16-unsaturated C(19) steroid from [4-(14)C]pregnenolone, the yield of radioactive 5-pregnene-3beta,20beta-diol increasing in the presence of added unlabelled andien-beta. 6. It is concluded that there may be two pathways leading to 16-unsaturated C(19) steroid formation from pregnenolone, one of these involving 5-pregnene-3beta,20beta-diol as an intermediate. Possible mechanisms are presented and discussed.  相似文献   

7.
The synthesis of labeled and non-labeled 3β,15α-dihydroxy-5-pregnen-20-one (V) and 3β, 15α-dihydroxy-5-androsten-17-one (XI) is described. Treatment of 15α-hydroxy-4-pregnene-3,20-dione (I) with acetic anhydride and acetyl chloride gave 3,15α-diacetoxy-3,5-pregnadien-20-one (II). The enol acetate (II) was ketalized by a modification of the general procedure to yield 3,15α-diacetoxy-3,5-pregnadien-20-one cyclic ethylene ketal (III) which was then reduced with NaBH4 and LiAlH4 to give 3β, 15α-dihydroxy-5-pregnen-20-one cyclic ethylene ketal (IV). Cleavage of the ketal group of IV gave V. Similarly, XI was prepared by starting with 15α-hydroxy-4-androstene-3,17-dione (VII). The (4-14C)-3β,15α-dihydroxy-5-pregnen-20-one was prepared by a modification of the above procedure in that the enol acetate (II)was directly reduced with NaBH4 and LiAlH4 to yield 5-pregnene-3β,15α,20β-triol (XIII) which was then oxidized enzymatically with 20β-hydroxysteroid dehydrogenase to V.  相似文献   

8.
After incubation of [ 4-14C )progesterone with cell-free homogenates of mouse mammary gland in the presence of NADPH, [14C]-labeled 4-pregnene-3α, 20α-diol was identified as a metabolite, besides 20α-hydroxy-4-pregnen-3-one which was the major metabolite.  相似文献   

9.
The present report concerns a gas chromatographic-mass spectrometric study on the urinary excretion of steroids during a virilizing malignant corticoadrenaloma resulting in the identification of thirty five steroids. They are: twelve 17-oxo-steroids, two 5α-androstane-3α,17-diols, two 5-androsten-3β,17-diols, four 5-androstane-3α,16,17-triols, the 5β-androstane-3α,11β,17α-triol, the 5α-androstane-α,3α,17α-triol, the 5-androsten-3β,16α,17β-triol, the 3α,16α-dihydroxy-5α-pregnan-20-one, the 3β,17α-dihydroxy5α-pregnan-20-one, the 5β-pregnane-3α,20α-diol, the 5-pregnene-3β,20α-diol, the 5-pregnene-3α,16α,20αtriol, the 5β-pregnane-3α,17,20α-triol, the 5-pregnene-3β,17,20α-triol and the 3α, 17,21 -trihydroxy-5β -pregnan-20-one.The quantitative assay of these metabolites done by g.l.c., showed that the 17-oxo-steroid excretion, averaging 111,9 mg/24 h, was linked to a major excretion of 3/α-hydroxy-5-androsten-17-one, 3α-hydroxy-5β,androstan-17-one, 3α,11β-dihydroxy-5α-androstan-17-one, 3α-hydroxy-5α,androstan-17-one and 3β,16α-dihydroxy-5-androsten-17-one averaging respectively 46.80, 30, 17.40, 6.10 et 5.25 mg/24 h. The relatively important metabolites are 5β-pregnane-3α,17,20α-triol, 5-androsten-3β,17β,diol, 5α-androstane-3/gb,16β,17α-triol, 5β-androstane-3α,16α,17β-triol, 5α-androstane-3α,17β-diol and 3α,17,21-trihydroxy-5β-pregnan-20-one averaging respectively 9.80, 7.60, 6.95, 3.25, 2.90 and 2.35 mg/24 h.The identification of three 5-androstane-3,16β,17α-triols confirms the results of other authors which showed their formation from the 4,16-androstadien-3-one.  相似文献   

10.
Isolation of two C(17)-C(20) rotamers of 20-methyl-20-(2-hydroxy-ethoxy)-5-pregnene-3β, 17α-diol has been reported. X-Ray analysis of a diacetate derivative of one of the “rotamers” shows that the actual structure is 3β-acetoxy-17aα-(2-acetoxyethoxy)-17α,17aβ-dimethyl-D-homo-5-androsten-17β-ol (C28H44O6). Thus, although this investigation refutes the existence of C(17)-C(20) rotamers, it suggests a possible new pathway for D-homo steroid synthesis.  相似文献   

11.
F V Nowak  H J Karavolas 《Steroids》1974,24(3):351-357
3H-20α-hydroxy-4-pregnen-3-one was incubated with anterior pituitaries from proestrous rats. The in vitro metabolic products, identified by reverse isotopic dilution and purification to constant specific activity, were 20α-hydroxy-5α-pregnan-3-one (23.0%) and 5α-pregnane-3α,20α-diol (11.4%). These are qualitatively the same metabolites which result from in vitro incubation of 20α-hydroxy-4-pregnen-3-one with medial basal hypothalamus. 68.8% of the recovered radioactivity remained as 20α-hydroxy-4-pregnen-3-one. These three compounds accounted for all of the recovered radioactivity.  相似文献   

12.
Testicular steroidogenesis in rams was examined by constant infusion (3 hr) of [1-14C]-acetate into the testicular artery of four conscious standing animals.The following steroids (in order of decreasing levels of [14C] labeling) were secreted by the testis and found in testicular tissue: testosterone, dehydroepiandrosterone, 3β-hydroxy-5-androsten-17-one, androstenediol, 5-androsten-3β,17β-diol and 17-hydroxy-4-pregnene-3,20-dione. In addition, [14C] labeling of 17,20α-dihydroxy-4-pregnen-3-one occurred in testicular tissue but not in blood. This in vivo system with the conscious standing ram demonstrated an operative Δ5 steroidal pathway to testosterone. The physiological significance of 17,20α-dihydroxy-4-pregnen-3-one is not yet explained in this species.  相似文献   

13.
The ability of bovine liver and fat to metabolize progesterone and also to form glucuronide conjugates with these progestins in vitro was investigated. Tissue supernatants were incubated with [4-14C] progesterone, UDP-glucuronic acid, and a NADPH generating system for 5 hr, at 37°C. Steroids were identified by thin-layer chromatography, high performance liquid chromatography, and recrystallization to a constant specific activity. The total original radioactivity which could not be removed by exhaustive ether extraction (presumptive conjugates) was 44.7 ± 14.2% in liver, 5.0 ± 3.6% in subcutaneous fat, and 3.7 ± 2.2% in kidney fat samples. Progestins identified in liver samples include 5β-pregnane-3α, 20α-diol (free and conjugate), 5β-pregnane-3α, 20β-diol (free and conjugate), 3α-hydroxy-5sB-pregnan-20-one (free and conjugate), 3β-hydroxy-5β-pregnan-20-one (free), 5β-pregnane-3, 20-dione (free), and progesterone (conjugate). Progestins identified in both the free and conjugate fractions of subcutaneous fat and kidney fat samples include progesterone, 3α-hydroxy-5β-pregnan-20-one, 20β-hydroxy-4-pregnen-3-one, and 20α-hydroxy-4-pregnen-3-one. Differences due to sex of bovine used were noted. These results confirm the ability of bovine liver to readily metabolize progesterone and form glucuronide conjugates of these compounds and suggest that adipose tissues take an active role in these actions in cattle.  相似文献   

14.
It has been shown that the cultured cells of Digitalis purpruea are capable of transforming progesterone (I) to 5α-pregnane-3,20-dione (II), 5α-pregnan-3β-ol-20-one (III), its glucoside (IV), 5α-pregnane-3β,20α-diol (V), its glucoside (VI), 5α-pregnane-3β,20β-diol (VII), its glucoside (VIII), Δ4-pregnen-20α-ol-3-one (IX), its glucoside (X), Δ-pregnen-20β-ol-3-one (XI) and its glucoside (XII). 5α-Pregnan-3β-ol-20-one glucoside (IV), 5α-pregnane-3β,20α-diol glucoside (VI), 5α-pregnane-3β,20β-diol glucoside (VIII), Δ4-pregnen-20α-ol-3-one glucoside (X) and Δ4-pregnen-20β-ol-3-one glucoside (XII) have been found for the first time as new metabolises by plant tissue cultures. A scheme for the biotransformation of progesterone (I) has been proposed, and the reduction and glucosidation activities distinctly have been observed in these cultured cells.  相似文献   

15.
Pregnenolone (3β-hydroxy-5-pregnen-20-one) and DHA (3β-hydroxy-5-androsten-17-one), substrates for 3β-hy-droxysteroid dehydrogenase (3β-HSD), with KM values of 15–40 nM, were ineffective inhibitors of 5-ene-3-ketosteroid isomerase (isomerase), with KI values >40 μM in each case. Progesterone and androstenedione (4-androstene-3, 17-dione), 3β-HSD inhibitors with KI values of 5.0 μM and 0.8 μM respectively, were also relatively ineffective inhibitors of isomerase, with KI values of 30 μM and 16.5 μM respectively. Exposure of microsomes to hydrogen peroxide, which significantly increases the KM for pregnenolone as a 3β-HSD substrate, had no effect on the KM for the isomerase substrate 5-pregnene-3, 20-dione.It is concluded that the data do not support the common site concept with regard to the conversion of pregnenolone to progesterone by human placental microsomes.  相似文献   

16.
Human cornea excised from patients with wounded eyes were incubated in vitro for a 5-day period in the presence of [4-14C]-progesterone. The following C21 steroid metabolites were identified by paper chromatography, derivative formation, and crystallizations to specific activities: 20α-hydroxy-4-pregnen-3-one, 20β-hydroxy-4-pregnen-3-one, and 5α-pregnan-3,20-dione.  相似文献   

17.
Two D-homosteroids were isolated from the hydrolyzate of 5β-pregnane -3α,20α-diol disulfate (II) when it was refluxed in 3N hydrochloric acid. The structures of these steroids have been elucidated as 17α-methyl-D-homo-5β-androstane-3α, 17aβ-diol (VI) and 17α-methyl-17aγb-chloro-D-homo-5β-androstan-3α-ol (VIII) by instrumental analyses. The former was identical with a synthetic specimen derived from 5β-pregnane-3α,20β-diol di-sulfate (IV) by uranediol rearrangement. The main hydrolyzates obtained were 17α-ethyl-17β-methyl-18-nor-5β-androst-13-en-3α-ol (V) and 5β-pregnane-3α, 20α-diol (III).  相似文献   

18.
C A Sherman  R F Hanson 《Steroids》1976,27(2):145-153
The two primary bile acids, cholic acid (3α,7α,12α-tri-hydroxy-5β-cholan-24-oic acid) and chenodeoxycholic acid (3α,7α-dihydroxy-5β-cholan-24-oic acid), are initially synthesized by way of identical precursors, and the point of divergence of this pathway is thought to occur at the intermediate 7α-hydroxy-4-cholesten-3-one. In order to test this hypothesis, bile fistula rats received simultaneous intra-venous infusions of 3H-7α-hydroxy-4-cholesten-3-one and 14C-cholesterol (5-cholesten-3β-ol). Assays of equal specific activities of the two bile acids from an infusion of 14C-cholesterol demonstrated the achievement of a steady state, and assays of equal specific activities from an infusion of 3H-7α-hydroxy-4-cholesten-3-one would-validate the above postulate. However, the infusion of 3H-7α-hydroxy-4-cholesten-3-one resulted in unequal specific activities in the bile acids of the rats investigated, with cholic acid always of a lower value. These results suggest that either 7α-hydroxy-4-cholesten-3-one is not the last common intermediate in the production of cholic acid and chenodeoxycholic acid, or that the infused bile acid intermediate was not metabolized in a fashion similar to that formed in the liver from cholesterol.  相似文献   

19.
A number of potential intermediates of lanosterol1 14α-demethylation have been synthesized for the first time and labelled with 3H. A direct comparison of the rates of conversion of each of these materials to cholesterol and 5α-cholest-7-en-3β-ol by a cell-free system from rat liver has been made. Although 5α-lanost-8-en-3β,32-diol and 3β-hydroxy-5α-lanost-8-en-32-al were converted to C27 sterols at a greater rate than was 5α-lanost-8-en-3β-ol, the apparent Km values were larger than those expected if these compounds were obligatory intermediates. 5α-Lanost-8-en-3β,15α-diol and 5α-lanost-8-en-3β,15β-diol were poorer precursors of cholesterol but each was extensively converted both to a more polar compound and to the corresponding 3β,15-diol diester.  相似文献   

20.
Progesterone-4-14C was extensively metabolized during incubation with dispersed trophoblast prepared from chorionic membranes of the 21-day sheep conceptus. Of the metabolites formed, 17,20α-dihydroxypregn-4-en-3-one, 20α-hydroxypregn-4-en-3-one, 20(β-hydroxypregn-4-en-3-one, 5α-pregnane-3α,17,20α-triol, 5β-pregnane-3ga, 17,20α-triol, 5β-pregnane-3g,20α-diol, 3β-hydroxy-5α-pregnan-20-one, 3α-hydroxy-5β-pregnan-20-one, 20β-hydroxy-5β-pregnan-3-one, 5α-pregnane-3,20-dione and 5β-pregnane-3,20-dione were identified. These findings indicate that the sheep conceptus acquires extensive steroid metabolizing capability very early in pregnancy.  相似文献   

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