Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.1.1.3 (HSD)
 3,464 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

3beta-hydroxysteroid dehydrogenase and NADH-ferricyanide reductase activities were localized at the ultrastructural level in amphibian interrenal (adrenocortical) cells previously fixed in a mixture of formaldehyde and glutaraldehyde. Potassium ferricyanide was used as an electron acceptor. Copper ferrocyanide deposits resulting from 3beta-HSD activity were seen in close association with the external faces of the membranes of the smooth endoplasmic reticulum. Very rare grains of precipitate appeared in mitochondrial cristae. The addition of phenazine methosulfate to the incubation medium had no effect on these localizations. The interrenal cells showed also a strong NADH-ferricyanide reductase activity. The copper ferrocyanide grains were abundant in the mitochondrial cristae and in the hyaloplasm, where they were not preferentially associated with the smooth endoplasmic reticulum.
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PMID:Electron microscopic localization of 3beta-hydroxysteroid dehydrogenase and NADH-ferricyanide reductase activities in amphibian interrenal cells. 30 25

A study of the ultrastructural localization of 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD), 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD), glucose-6-phosphate dehydrogenase (G-6-PD), beta-hydroxybutyrate dehydrogenase (beta-HBD), NADH diaphorase (NADH-D) and NADPH diaphorase (NADPH-D) in the guinea-pig testis is reported. The procedures employed included short immersion or perfusion fixation with aldehydes followed by incubation of small blocks in a tetrazolium salt or a ferricyanide medium. The effects of incubation conditions were investigated, and a reaction medium for the ultracytochemical demonstration of 11 beta-HSD is described. Using suitable controls, evidence for the specificity of the cytochemical reactions is presented. It was found that all the enzymes studied were present in both the Leydig and Sertoli cells of the guinea-pig testis and that the intracellular distribution pattern for each enzyme was independent of the cell type. Using tetrazolium salt techniques, both 3 beta-HSD and 11 beta-HSD activities were localized on or in membranes of smooth endoplasmic reticulum and within the mitochondria. With the ferricyanide techniques, G-6-PD activity was found to be associated mainly with the smooth endoplasmic reticulum membranes, while beta-HBD activity was limited to mitochondria. With both the tetrazolium salt and ferricyanide techniques, the reaction products for NADH-D and NADPH-D activities showed localizations which were similar to those observed for the steroid dehydrogenases.
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PMID:The ultrastructural localization of the enzymes related to steroid hormone metabolism in the guinea-pig testis. 42 99

The ovary of the domestic pigeon, Columba livia, has been assayed histochemically for the localization of delta 5-3 beta-hydroxysteroid dehydrogenase (delta 5-3 beta-HSDH), 17 beta-hydroxysteroid dehydrogenase (17 beta-HSDA), 11 beta-hydroxysteroid dehydrogenase (11 beta-HSDH), glucose-6-phosphate dehydrogenase (G6P-DH) and NADH-diaphorase activities during different periods of the reproductive cycle. delta 5-3 beta-HSDH, 17 beta-HSDH, 11 beta-HSDH, G6P-DH and NADH-diaphorase activity was found in the theca interna of growing, atretic and postovulatory follicles, the granulosa of ovulatory, atretic and postovulatory follicles, and interstitial gland cells during the pre-incubation and the laying periods. During the incubation and squab feeding periods only delta 5-3 beta-HSDH, G6P-DH and NADH-diaphorase activities were observed in the above mentioned cells. The steroidogenic potential of atretic follicles depends upon the type of atresia a follicle undergoes.
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PMID:Steroid synthesizing cellular sites in the ovary of the domestic pigeon Columba livia (Gmelin): a histochemical study. 45 38

By recording the incubation time needed for initial appearance of the red and blue formazans the reliability of the histochemical method for 3beta-HSD was investigated: 1. Prefixation of small tissue blocks with 1% W/V methanol-free formaldehyde (pH=7.2) for up to 30 min preserved morphological integrity as well as maximal enzyme activity. Moreover, the substantivity of formazans and lipids was enhanced. 2. Commercial available glutaraldehyde (pH=7.2) induced SH groups in the tissue (even at 0.1% W/V for 5 min) thereby enhancing the Nothing dehydrogenase reaction. 3. Preextraction of lipids with acetone for 20 min at -30 degree C caused no loss of activity and was an inevitable step if a reliable activity pattern had to be achieved (e.g. in interstitial cells). 4. No diffusion of enzyme was noticed within 30 min of preincubation in phosphate buffer (0.2 M, pH=7.2) at 20 degree C. 5. By using the double-section incubation method no diffusion of 3beta-HSD or rediffusion of NADH or PMSH could be noticed withn 45 min of incubation, provided that low concentrations of NAD (0.1 mg/ml) and PMS (0.003 mg/ml) were balanced against the concentration of Nitro BT (0.5 mg/ml) or Tetranitro BT (1.0mg/ml). 6. The utlity of different inhibitors of alkaline phosphomonoesterase was tested and discussed. 7. By inhibiting alkaline phosphomonoesterase with 0.1 mM of L-p-bromotetramisole or 16 mM of beta-glycerophosphate, 3beta-HSD was shown to be exclusively NAD-linked. 8. Levamisole was a potent inhibitor of NADH-tetrazolium reductase as well as 3 beta-HSD, but not of NADPH-tetrazolium reductase. 9. 3beta-HSD possess SH groups requisite for the activity as this enzyme was totally inhibited by N-ethyl maleimide. 10. Whether alcohol dehydrogenases may use steroids as substrate is discussed; It is concluded that preextraction (by acetone) and/or the use of an inhibitor of alcohol dehydrogenase (1,10-phenanthroline) has to be performed. 11. Propylene glycol was a poor solvent for all substrates and was itself an excellent substrate for alcohol dehydrogenase. 12. Specifications for the ideal solvent of steroid substrates in the histochemical practice are proposed. DMSO showed to be promising as a steroid solvent (e.g. extraction of formazans was considerably lower as compared to DMF). 13. The utilization of substrates was descending in the following order (using 1 mM and 0.1 ml/ml of either DMF or DMSO): epiandrosterone, methandriol, dehydroepiandrosterone and pregnenolone. 14. If DMSO was used as solvent for pregnenolone (but not for the other substrates tested) an evident increase of activity was recorded as compared to DMF.
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PMID:Histochemistry of 3beta-hydroxysteroid dehydrogenase in rat ovary. I. Amethodological study. 55 64

Adult rats of both sexes were either gonadectomized or hypophysectomized and gonadectomized. Three to eight weeks later they were treated for 14 consecutive days with oil or with 75 or 200 mug testosterone propionate (TP) per 100 g body weight. The animals were killed and for each sex the gonadectomized animals were compared with the hypophysectomized-gonadectomized animals as far as their NADPH- and NADH-dependent 3alpha-hydroxy-steroid dehydrogenases (3alpha-HSD) in renal microsomes, transcortin levels in serum and five organ weights relative to total body weight were concerned. For two of the latter, i.e. the relative kidney and prostatic weights, no significant differences were found. Transcortin levels, relative adrenal weights and renal NADPH-dependent 3alpha-HSD activities were higher in oil-treated gonadectomized animals than in oil-treated hypophysectomized-gonadectomized animals. The opposite was found for the relative weights of uterus and seminal vesicles and renal NADH-dependent 3alpha-HSD activities. These differences between gonadectomized and hypophysectomized-gonadectomized animals disappeared after TP treatment as far as transcortin levels were concerned but remained for the five other parameters. After gonadectomy sexual differences subsisted for all parameters studied. But whereas intact male rats had higher NADH-dependent 3alpha-HSD activities than female rats the opposite was found after gonadectomy. After gonadectomy plus hypophysectomy the between sex differences disappeared as far as transcortin levels were concerned but remained in the other parameters studied.
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PMID:Effects of testosterone mediated or modulated by pituitary factors. 119 29

3 alpha-Hydroxysteroid dehydrogenase (3 alpha-HSD) was purified greater than 500-fold from human liver cytosol. The purification was monitored using 5 beta-[3H]dihydrocortisol (5 beta-DHF) as substrate. Electrophoretically homogeneous enzyme was obtained using a procedure that involved ammonium sulfate precipitation and three successive column chromatography steps: DEAE-cellulose, hydroxylapatite and Blue-Sepharose. The enzyme is a monomer since the native molecular weight was found to be 37,000, using a calibrated Sephadex G-75 column, and the denatured subunit molecular weight was determined to be 38,500, by polyacrylamide gel electrophoresis in sodium dodecyl sulfate. The enzyme had a pI of 5.6-5.9. The 3-ketosteroids: cortisol, testosterone, progesterone and androstenedione, were not substrates for 3 alpha-HSD indicating that a saturated 4,5 double bond was required for substrate activity. The conformation at the 5 position, however, did not influence substrate activity since 5 alpha- and 5 beta-DHF and 5 alpha-dihydrotestosterone were all reduced at similar rates. The purified enzyme preferred NADPH to NADH as a cofactor and showed a broad peak of activity in the pH range of 6.8-7.4. The apparent Km for 5 beta-DHF was 18 microM. The enzyme was markedly stabilized by 50 mM phosphate buffer containing 10 to 20% glycerol at 4 degrees C. Freezing and thawing of the enzyme resulted in a large loss of activity during early stages of the purification. This is the first report of the purification to homogeneity of 3 alpha-HSD from human tissue.
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PMID:Purification and properties of human hepatic 3 alpha-hydroxysteroid dehydrogenase. 139 Feb 84

3 Alpha-hydroxysteroid dehydrogenase (3 alpha-HSD) from Pseudomonas testosteroni was shown to reduce the xenobiotic carbonyl compound metyrapone (MPON). Reversely, MPON reductase purified from mouse liver microsomes and previously characterized as aldehyde reductase, was competitively inhibited by 3 alpha-HSD steroid substrates. For MPON reduction both enzymes can use either NADH or NADPH as co-substrate. Immunoblot analysis after native and SDS gel electrophoresis of 3 alpha-HSD gave a specific crossreaction with the antibodies against the microsomal mouse liver MPON reductase pointing to structural homologies between these enzymes. In conclusion, there seem to exist structural as well as functional relationships between a mammalian liver aldehyde reductase and prokaryotic 3 alpha-HSD. Moreover, based on the molecular weights and the co-substrate specificities microsomal mouse liver MPON reductase and Pseudomonas 3 alpha-HSD seem to be members of the short-chain alcohol dehydrogenase family.
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PMID:Functional and immunological relationships between metyrapone reductase from mouse liver microsomes and 3 alpha-hydroxysteroid dehydrogenase from Pseudomonas testosteroni. 155 29

A 3 alpha-reducing activity of 5 alpha-dihydrotestosterone (5 alpha-DHT) was found in pig adrenal cytosol. The enzyme (3 alpha-hydroxysteroid dehydrogenase: 3 alpha-HSD) has been purified to homogeneity from pig adrenal cytosol by ammonium sulfate precipitation followed by DEAE-cellulose, 2', 5'-adenosine diphosphate-Sepharose and Sephadex G-100 column chromatographies. The molecular weight was estimated to be 33,000 and 39,000 by gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Isoelectric point was estimated to be 8.5 by isoelectric focusing. The Km and Vmax values for 5 alpha-DHT in the reduction were 10.2 microM and 10.6 nmol/min/mg. The enzyme utilized reduced nicotinamide adenine dinucleotide phosphate (NADPH) or reduced nicotine amide adenine dinucleotide (NADH) in the reduction as a cofactor, but it preferentially required NADPH rather than NADH. Furthermore, the purified enzyme catalyzed not only 3 alpha-reduction of 5 alpha-DHT (9.65 nmol/min/mg), but also catalyzed 20 alpha-reduction of 17 alpha-hydroxyprogesterone (0.58 nmol/min/mg). The enzyme activity of 3 alpha-HSD was strongly inhibited by Hg2+, but it was not inhibited by medroxyprogesterone acetate and some anti-inflammatory agents. No remarkable differences was demonstrated between 3 alpha-HSD and 20 alpha-HSD activity under the influence of heat treatment, divalent cation, anti-inflammatory agents and some inhibitory steroids. These results strongly suggest that 3 alpha-HSD purified from pig adrenal cytosol is a bi-functional enzyme catalyzing 3 alpha- and 20 alpha-HSD activities.
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PMID:[Purification and some properties of 3 alpha-hydroxysteroid dehydrogenase from pig adrenal cytosol]. 180 59

17 Beta-Hydroxysteroid dehydrogenase (17 beta-HSD) is present in multiple forms in human breast tissue. One soluble form, with a molecular weight of approximately 35 kDa, was purified to near homogeneity from whole normal breast tissue. This form catalysed the oxidation of oestradiol and the reduction of oestrone, with NADP+ and NADPH as the preferred coenzymes. Three other soluble forms with higher molecular weights (in the range 50-80 kDa) were isolated. They catalysed the oxidation of oestradiol but not the reduction of oestrone, and all of them had properties very different from those of the low molecular weight enzyme. Activities of 17 beta-HSD were measured in particulate and soluble fractions from normal breast adipose and non-adipose tissues, and from breast tumours obtained from post-menopausal women, in the oxidative direction with NAD+ and NADP+ as coenzymes and in the reductive direction with NADH and NADPH as coenzymes. Particulate fractions from tumours had much higher oxidative and reductive activities than those from normal tissues. Soluble fractions from tumours had higher oxidative activities than those from the normal tissues but similar reductive activities. The major soluble form of 17 beta-HSD in adipose tissue was the 35 kDa enzyme which had both oxidative and reductive activities. In contrast, the majority of the soluble activity in non-adipose tissue was due to enzymes, with molecular weights in the range 50-80 kDa, which had oxidative activity only. The soluble fractions of tumours, like those of non-adipose tissue, contained enzymes with molecular weights in the range 50-80 kDa. In addition, they contained a 35 kDa enzyme with properties different from those of the enzyme with the same molecular weight present in adipose tissue.
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PMID:17 Beta-hydroxysteroid dehydrogenases in human breast tissues: purification and characterization of soluble enzymes and the distribution of particulate and soluble forms in adipose, non-adipose and tumour tissues. 189 41

Rat liver 3 alpha-hydroxysteroid dehydrogenase (3 alpha-HSD) (EC 1.1.1.50) is an NAD(P)(+)-dependent oxidoreductase that is potently inhibited at its active site by non-steroidal anti-inflammatory drugs (NSAIDs). Initial-velocity and product-inhibition studies performed in either direction at pH 7.0 are consistent with a sequential ordered Bi Bi mechanism in which pyridine nucleotide binds first and leaves last. This mechanism is supported by fluorescence titrations of the E-NADH complex, and by the failure to detect the binding of either [3H]androsterone or [3H]androstanedione to free enzyme by equilibrium dialysis. Dead-end inhibition studies with NSAIDs also support this mechanism. Initial-velocity studies with indomethacin show that this drug is an uncompetitive inhibitor against NAD+, but a potent competitive inhibitor against androsterone, indicating the ordered formation of an E.NAD+.indomethacin complex. Calculation of the individual rate constants reveals that the binding and release of pyridine nucleotide is rate-limiting and that isomerization of the central complex is favoured in the forward direction. Equilibrium dialysis experiments with [14C]indomethacin reveal the presence of two abortive NSAID complexes, a high-affinity ternary complex corresponding to E.NAD+.indomethacin (Kd = 1-2 microM for indomethacin) and a low-affinity binary complex corresponding to E.indomethacin (Kd = 22 microM for indomethacin). Since indomethacin has a low affinity for free enzyme, the formation of this abortive binary complex does not complicate kinetic measurements which are made in the presence of NAD+, but may contribute to the inhibition of the enzyme by NSAIDs. Using either pro-R-[4-3H]NADH or pro-S-[4-3H]NADH as cofactor, radiolabelled androsterone was formed only when the pro-R-[4-3H]NADH was used, confirming that purified 3 alpha-HSD is a Class A dehydrogenase.
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PMID:The kinetic mechanism catalysed by homogeneous rat liver 3 alpha-hydroxysteroid dehydrogenase. Evidence for binary and ternary dead-end complexes containing non-steroidal anti-inflammatory drugs. 189 69


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