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Query: UMLS:C0338671 (Steroids)
 9,479 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A mixture of 3H-testosteron (T) and 14C-4-androstene-3, 17-dione (A) was injected intravenously into 2 (I and II) rhesus monkeys (Macaca mulatta). A third monkey (III) was injected with 3H-T only. Urine and bile samples were collected at intervals for 6 hours following the injection. The excretion, conjugation and aglycone metabolites of the steroids injected were studied using these samples. Of the injected dose, animal I (male) excreted 32% 3H and 23% 14C in the bile and 30% 3H and 21% 14C in the urine in 6 hours. Animal II (female), however, had a comparatively higher biliary excretion (66% 3H, 40% 14 C), but a urinary excretion (18% 3H, 13% 14C) comparable to that of animals I and III. The averages in the bile of the 3 animals were: unconjugated compounds 3%, glucosiduronates 78%, sulfates 9%, sulfoglucosiduronates 5% and disulfates 3%; and in urine, 5% unconjugated, 92% glucosiduronates and 3% sulfates. The aglycones obtained following hydrolysis were separated gy chromatography on Lipidex 5000, further purified by thin layer and paper chromatography and identified by co-crystallization. The major matabolites from 3H-T were androsterone and 5beta-androstane-3alpha,17beta-diol, whereas that from 14C-A was androsterone. Other metabolites identified were: etiocholanolone (3beta-hydroxy-5-beta-androstan-17-one); T, epitestosterone (epi-T), (17alpha-hydroxy-4-androsten-3-one); epiandrosterone (3-beta-hydroxy-5alpha-androstan-17-one) and 5alpha-androstane-3alpha, 17beta-diol. The results indicate that while androgen metabolism in the rhesus monkey is similar to that of the baboon and human in conjugate and metabolite formation, the rate of excretion was significantly different, resembline more closely that of the baboon than the human.
Steroids 1978 May
PMID:Androgen metabolism in the rhesus monkey. 9 7

Cultures of Sertoli cells isolated from testes of 18-and 36-day-old Long Evans rats were used to investigate their capacity to metabolize testosterone and the effect of FSH on such metabolism. Three different approaches were used: 1) investigation of the metabolism of radiolabeled testosterone under saturating substrate conditions; 2) study of the metabolism of radiolabeled testosterone utilizing trace amounts of high specific activity substrates; 3) the utilization of radioimmunoassay for measurement of estradiol-17 beta. The following steroids were isolated and identified by recrystallization to constant specific acitvity from the control and FSH-treated cultures; testosterone (unconverted substrate), androstenedione, dihydrotestosterone, 3 alpha-hydroxy-5 alpha-androstan-17-one and 5 alpha-androstane-3 alpha, 17 beta-diol. Radioimmunoassay data suggests that the Sertoli cells produce an estradiol-17 beta-like compound from unlabeled testosterone and that this production is stimulated by FSH. However, the radioactive metabolite from all our studies that behaved chromatographically like estradiol--17 beta failed to crystallize to constant specific activity, while in each experiment, authentic radiolabeled estradiol-17 beta added as recovery tracer did. The data demonstrate that : 1) cultures of Sertoli cells from immature rats have 5 alpha-reductase, 3 alpha- and 17 beta-hydroxysteroid oxidoreductase activities; 2) these enzymes may be affected by FSH; 3) based on radiolabeled metabolic techniques, Sertoli cells were unable to biotransform testosterone to estradiol-17 beta even in the presence of FSH.
Steroids 1979 May
PMID:In vitro metabolism of testosterone by cultured Sertoli cells and the effect of FSH. 31 14

In addition to using radioimmunoassays for the determination of estrogens and other steroids, the possibility of using mass fragmentography for analysis was investigated. t-Butyldimethylsilyl chloride was selected as a reagent for derivatisation because it forms rather stable silylethers. In all the mass-spectra obrained from the steroid derivatives, one pronounced peak suitable for mass fragmentography was always present. Some of the spectra of the investigated estrogens, as well as testosterone, 3 alpha-hydroxy-5 alpha-androstan-17-one and 17 alpha-methyl-17 beta-hydroxy-5 alpha-androstan-3-one are discussed. The stability of various t-butyldimethylsilylethers and the rate of enolization of testosterone and progesterone in the presence of the silylation-agent under different conditions were established.
Steroids 1979 Apr
PMID:Mass spectrometry and stability of t-butyldimethylsilylethers of some estrogens and androstanes. 44 30

Rat ventral prostate and liver were investigated for the binding in vitro to particulate fractions and for the metabolism of 5 alpha-androstane-3 beta, 17 beta-diol. Comparative investigations were carried out on the metabolism of 5 alpha-androstane-3 alpha, 17 beta-diol. Preparations of the liver were investigated in order to establish the organ specificity of the method. In the prostate, the bulk of the metabolites of 5 alpha-androstane-3 beta, 17 beta-diol was present as steroids of high polarity. Of the less polar metabolites, 17 beta-hydroxy-5 alpha-androstan-3-one, 3 beta-hydroxy-5 alpha-androstan, 17-one and 5 alpha-androstane-3 alpha, 17 beta-diol were detectable. The binding of a 5 alpha-androstane-3 beta, 17 beta-diol to mitochondria and microsomes was unspecific. In the liver, among the less polar metabolites, 3 beta-hydroxy-5 alpha-androstan-17-one was the main metabolite, and the binding was unspecific. The main metabolite in the prostate homogenate of 5 alpha-androstane-3 alpha, 17 beta-diol was 17 beta-hydroxy-5 alpha-androstan-3-one. The portion of highly polar steroids was very low. The portion of unmetabolized hormone was distributed almost equally among the different cell preparations except the nuclei, in which 17 beta-hydroxy-5 alpha-androstan-3-one was higher and 5 alpha-androstane-3 alpha, 17 beta-diol was lower than in the remaining cell fractions.
Steroids 1979 Aug
PMID:Metabolism and binding in vitro of 5 alpha-androstane-3 beta, 17 beta-diol and of 5 alpha-androstane-3 alpha, 17 beta-diol in cell fractions of rat ventral prostate and liver. 49 56

The epididymis of adult rats metabolizes 3H 5alpha-androstane-3alpah,17beta-diol (3alpha-diol) by experiments in vitro. After incubation of tissue slices at 37 degrees C for 2 hours, 2% of the radioactivity was found in the water-soluble fraction whereas 98% was found to be ether soluble (free steroids). Further investigation of the free steroids showed the following to be present: 3alpha-diol 39.9%, DHT (17beta-hydroxy-5alpha-androstan-3-one) 33.7%, androsterone (3alpha-hydroxy-5alpha-androstan-17-one) 9.2%, 3beta-diol (5alpha-androstane-3beta,17beta-diol) 2.6%, 5alpha-A-dione (5alpha-androstan-3,17-dione) 1.1%, delta 16-3alpha-ol (5alpha-androst-16-en-3alpha-ol) 1.0%, delta16-3beta-ol (5alpha-androst-16-en-3beta-ol) 2.6%, delta 16-3-one (5alpha-androst-16-en-3-one) 2.9%, and polar compounds 3.3%. When segments of the epididymis (caput and cauda) were incubated in the same way, qualitatively similar metabolites were formed but a greater amount of 3alpha-diol was metabolized by the cauda epididymis. This increase was mainly accounted for by an increased formation of delta 16 compounds (14.3% in cauda, 4.3% in caput). This is most probably due to the presence of larger numbers of mature spermatozoa, which, as we have previously shown, form delta16 steroids from 3alpha-diol and DHT (5).
Steroids 1977 Oct
PMID:Androgen metabolism by rat epididymis. Metabolic conversion of 3H 5alpha-androstane-3alpha,17beta-diol, in vitro. 60 59

Androsterone (3alpha-hydroxy-5alpha-androstan-17-one), 5alpha-androstane-3alpha, 17beta-diol and 5alpha-androstane-3beta, 17beta-diol were conjugated at C-16 through sulfur to bovine and human serum albumin. Rabbits injected with these conjugates produced antibodies suitable for radioimmunoassays of these hormone metabolites. Samples were purified on Sephadex LH-20 columns. Levels of these steroids were measured in a rat blood serum pool and in ovarian tissue extract pools.
Steroids 1977 Nov
PMID:Radioimmunoassays for androsterone, 5alpha-androstane-3alpha, 17beta-diol and 5alpha-androstane-3beta, 17beta-diol. 61 34

A simple procedure is described for solubilizing microsomal 3beta-hydroxysteroid dehydrogenase (3beta-HSD). Microsomes from rat adrenals or from testicular interstitial cells were incubated for 1 or 2 h at 0 C in a buffer containing NaCl followed by overnight storage at -20 C. Maximum solubilization of 3beta-hydroxy-5beta-androstan-17-one-HSD (androstane-3beta-HSD) was obtained by incubating adrenal microsomes with 1 M NaCl and interstitial cell microsomes with 2 M NaCl. Incubation with NaCl for 1 or 2 h resulted in maximum solubilization; incubation with NaCl for 4, 8 or 24 h did not change the amount of enzyme solubilized. From adrenal microsomes incubated with 1 M NaCl, up to 80% (105.7 millimicron/mg microsomes) of the total androstane-3beta-HSD activity was recovered in the supernatant following centrifugation at 130,000 x g for 1 h. The maximum amount of androstane-3beta-HSD solubilized from interstitial cell microsomes was 56% (29.5 millimicron/mg microsomes) at 2 M NaCl. The "solubilized" androstane-3beta-HSD was retarded when chromatographed on a Sephadex G-200 column and it did not pellet out when centrifuged at 130,000 x g for 15 h. KCL appeared to be equally effective in solubilizing androstane-3beta-HSD from microsomes. Other steroid dehydrogenase activities such as pregnanolone-HSD and 3beta-hydroxy-5alpha-androstan-17-one-HSD were also found in the 130,000 x g supernatant.
Steroids 1977 Nov
PMID:A simple procedure for solubilizing 3beta-hydroxysteroid dehydrogenase from microsomes of rat adrenals and testis interstitial cells. 61 35

Testosterone-1,2-3H was injected intravenously into a male dog with a bile fistula and bile and urine collected. The radioactivity was excreted preponderantly in bile (52% of the injected dose) in 6 hours; only 12% appeared in the urine. Methods to study the biliary metabolites of testosterone in this and other animals were developed. Satisfactory conjugate patterns were obtained by fractionation on DEAE-Sephadex A-25 columns using two different elution systems. In addition to an unchanged fraction, six different monoglucuronide fractions were separated. No other conjugates were isolated. Lipidex 5000 column chromatography, TLC and paper chromatography were used for the isolation and purification of aglycone metabolites, which were further identified by co-crystallization methods. The biliary metabolites of testosterone were epiandrosterone (3beta-hydroxy-5alpha-androstan-17-one), etiocholanlone (3alpha-hydroxy-5beta-androstan-17-one), 5alpha-androstan-3beta, 17beta-diol, 5beta-androstan-3alpha, 17beta-diol and 5beta-androstan-3beta,17beta-diol.
Steroids 1978 Feb
PMID:Testosterone metabolites in dog bile. 66 66

3H-Testosterone (3H-T) plus 14C-androst-4-ene-3,17-dione (A-dione) and 3H-epi-testosterone (17alpha-hydroxy-4-androsten-3-one) (epiT) plus 14C-T were injected intravenously into two male sheep with bile fistulae, respectively. Urine and bile samples were collected at intervals for 4-8 hours and analyzed by the use of DEAE-Sephadex A-25 and Lipidex 5000 columns, TLC, and paper chromatography; the aglycones were identified by co-crystallization with authentic standards. Five fractions were obtained from urine and bile: unconjugated, glucosiduronates, sulfates, sulfo-glucosiduronates and disulfates. In urine, the major conjugates were glucosiduronates, while sulfates predominated in bile. About 80-90% of recovered radioactivity was found to be either glucosiduronates or sulfates. Among the metabolites identified, epi-T was the principal one, accounting for 10-15% of the administered doses. Conversion to 17alpha-hydroxysteroids thus appears to be a major route of metabolism of the androgens administered in sheep. Other metabolites in the glucosiduronate and sulfate fractions were androsterone, etiocholanolone (3alpha-hydroxy-5beta-androstan-17-one), 5beta-androstane-3alpha,17beta-diol, two unknown diols and polar metabolites. The results indicated that androgen metabolism is somewhat unusual in sheep, as compared with other animals and the human.
Steroids 1978 Oct
PMID:Androgen metabolism in sheep. 71 26

The metabolism of 1,2-3H-androstenedione was studied in 2 cell lines, MCF-7 (estrogen responsive) and BT-20 (estrogen nonresponsive) over 48 hrs. Water soluble and unconjugated metabolites were separated by solvent partition and the former was submitted to chromatography on Sephadex LH-20 and enzyme hydrolysis. The resulting unconjugated steroids were separated by paper chromatography and identities were established by reverse isotope dilution. The unconjugated steroids initially obtained were separated by chromatography and identified by reverse isotope dilution. About 70% of the androstenedione was metabolized by both cell lines. However, the respective conversions to conjugates by MCF-7 and BT-20 were 31% and 0.32%. In the former, glucosiduronates predominated (94%) and consisted of androsterone (55%), etiocholanolone (9.4%) and androstanediol (5alpha-androstane-3alpha,17beta-diol) (9.3%). Androsterone comprised most of the unconjugated metabolites in both cell lines. Androstanediol was found in both cell lines, 2% in MCF-7 and 12% in BT-20. Testosterone, 5alpha-androstane-3,17-dione and 3beta-hydroxy-5alpha-androstan-17-one were isolated only from MCF-7. The metabolism of 3H-estriol was studied in a similar way. Both cell lines produced about equal amounts of estriol-3-sulfate (9%) and a compound with properties of estriol-3-glucosiduronate (0.15--0.5%). The results worthy of emphasis are: 1. The far greater conjugation of androgens exhibited by the MCF-7 cell lines as compared to the BT-20 cell lines; 2. In MCF-7, the high conversion of androstenedione to etiocholanolone (glucosiduronate form), a metabolite reported to form only in liver and sebaceous cysts; 3. The possible formation in both cell lines of estriol-3-glucosiduronate, normally a metabolite of the intestine.
Steroids 1978 Dec
PMID:Steroid metabolism in human breast cancer cell lines. 73 1


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