HISTOCHEMICAL DEMONSTRATION OF 20β-Hydroxysteroid DEHYDROGENASE

Baillie, A. H.; Calman, Kenneth C.; Ferguson, M.M.; Hart, D. McK.

doi:10.1677/joe.0.0320337

Cited by 17 publications

(8 citation statements)

References 6 publications

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“…On the contrary, from the fact that the specific activity of the enzyme in the supernatant fluid of X-irradiated testes of rats, in which spermatogenesis was completely destroyed, was higher than that of intact rats, the location of the 20a-hydroxysteroid dehydrogenase was thought to be in relatively radioresistant cells, such as interstitial cells and others (4). The 20/3-hydroxy steroid dehydrogenase was reported to be located in the interstitial cells of testicular tissue of mouse and man by histochemical examination (32), and 20a-hydroxysteroid dehydrogenase in ovary was reported to be concentrated in corpora lutea exclusively (33). From the results described in this report, 20a-hydroxysteroid dehydrogenase activity was observed to be even in the soluble fraction of immature rat testes, in which no spermatogenesis occurs.…”

Section: Discussionsupporting

confidence: 49%

Bioconversion of Steroids in Immature Rat Testesin Vitro1

Itoh¹,

Tamaoki²

1966

Endocrinology

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Among the testicular enzymes related to steroid bioconversion, the A B -3/3-hydroxysteroid dehydrogenase, together with the isomerase, and the 17/3-hydroxysteroid dehydrogenase activities per testis were found to be low in the testicular microsomes of immature rats (27-day-old), in comparison with those of adult rats (90-day-old), while the 17«-hydroxylase and the pregnene-Ci7-Coo lyase activities were found to be relatively active in immature rat testes. After incubation of 17 a-hydroxy progesterone and androst-4-ene-3,17-dione separately with the testicular microsomes of immature rats, 3«, 17«-dihydroxy-5«-pregnan-20-one was obtained as one of the major metabolites of 17a-hydroxyprogesterone, and 5a-androstane-3,17-dione, 3«-hydroxy-5a-androstan-17-one, and 3/3-hydroxy-5«-androstan-17-one as metabolites of both substrates. The enzymic pattern unique to the testes of immature rats would seem to be the significantly strong activities of the A 4 -androstene and -pregnene-5a-reductase, the 5a-androstane-3«-,

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Section: Discussionsupporting

confidence: 49%

Bioconversion of Steroids in Immature Rat Testesin Vitro1

Itoh¹,

Tamaoki²

1966

Endocrinology

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“…The presence of testicular 11βHSD activity was first noted in the 1960's by enzyme histochemical labeling of Leydig cells in cryostat sections [40]. Enzyme histochemistry detects the oxidative component of oxidoreductases, with electron transfer to the enzyme's pyridine cofactor forming NADPH and further electron donation to diaphorase (a ubiquitouslyexpressed enzyme), and finally to the tetrazolium salt dye, resulting in deposition of blue formazan crystals [40].…”

Section: A Rapid Action Of Glucocorticoids Via 11βhsd1mentioning

confidence: 99%

“…Enzyme histochemistry detects the oxidative component of oxidoreductases, with electron transfer to the enzyme's pyridine cofactor forming NADPH and further electron donation to diaphorase (a ubiquitouslyexpressed enzyme), and finally to the tetrazolium salt dye, resulting in deposition of blue formazan crystals [40]. When an antibody to 11βHSD1 was produced [41], immunocytochemical staining revealed abundant expression of type 1 protein in rat Leydig cells postnatally [42].…”

Section: A Rapid Action Of Glucocorticoids Via 11βhsd1mentioning

confidence: 99%

Rapid mechanisms of glucocorticoid signaling in the Leydig cell☆

Lian

Lin

et al. 2008

Steroids

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Stress-mediated elevations in circulating glucocorticoid levels lead to corresponding rapid declines in testosterone production by Leydig cells in the testis. In previous studies we have established that glucocorticoids act on Leydig cells directly, through the classic glucocorticoid receptor (GR), and that access to the GR is controlled prior to the GR by a metabolizing pathway mediated by the type 1 isoform of 11β-hydroxysteroid dehydrogenase (11βHSD1). This enzyme is bidirectional (with both oxidase and reductase activities) and in the rat testis is exclusively localized in Leydig cells where it is abundantly expressed and may catalyze the oxidative inactivation of glucocorticoids. The predominant reductase direction of 11βHSD1 activity in liver cells is determined by an enzyme, hexose-6-phosphate dehydrogenase (H6PDH), on the luminal side of the smooth endoplasmic reticulum (SER). Generation of the pyridine nucleotide cofactor NADPH by H6PDH stimulates the reductase direction of 11βHSD1 resulting in increased levels of active glucocorticoids in liver cells. Unlike liver cells, steroidogenic enzymes including 17β-hydroxysteroid dehydrogenase 3 (17βHSD3) forms the coupling with 11βHSD1. Thus the physiological concentrations of androstenedione serve as a substrate for 17βHSD3 utilizing NADPH to generate NADP+, which drives 11βHSD1 in Leydig cells primarily as an oxidase; thus eliminating the adverse effects of glucocorticoids on testosterone production. At the same time 11βHSD1 generates NADPH which promotes testosterone biosynthesis by stimulating 17βHSD3 in a cooperative cycle. This enzymatic coupling constitutes a rapid mechanism for modulating glucocorticoid control of testosterone biosynthesis. Under stress conditions, glucocorticoids also have rapid actions to suppress cAMP formation thus to lower testosterone production.

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“…A staining solution is applied onto the sample to conduct a chromogenic reaction (Baillie et al 1965(Baillie et al , 1966. The staining solution contains a substrate (e.g., dehydroepiandrosterone for 3β-HSD; testosterone for 17β-HSD; androsterone for 3α-HSD), nicotinamide adenine dinucleotide (NAD + ), and NBT/BCIP.…”

Section: Methods For Studies Of Steroidogenesismentioning

confidence: 99%

Methods for the Study of Gonadal Development

Piprek

2016

Results and Problems in Cell Differentiation

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Current knowledge on gonadal development and sex determination is the product of many decades of research involving a variety of scientific methods from different biological disciplines such as histology, genetics, biochemistry, and molecular biology. The earliest embryological investigations, followed by the invention of microscopy and staining methods, were based on histological examinations. The most robust development of histological staining techniques occurred in the second half of the nineteenth century and resulted in structural descriptions of gonadogenesis. These first studies on gonadal development were conducted on domesticated animals; however, currently the mouse is the most extensively studied species. The next key point in the study of gonadogenesis was the advancement of methods allowing for the in vitro culture of fetal gonads. For instance, this led to the description of the origin of cell lines forming the gonads. Protein detection using antibodies and immunolabeling methods and the use of reporter genes were also invaluable for developmental studies, enabling the visualization of the formation of gonadal structure. Recently, genetic and molecular biology techniques, especially gene expression analysis, have revolutionized studies on gonadogenesis and have provided insight into the molecular mechanisms that govern this process. The successive invention of new methods is reflected in the progress of research on gonadal development.

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HISTOCHEMICAL DEMONSTRATION OF 20β-Hydroxysteroid DEHYDROGENASE

Cited by 17 publications

References 6 publications

Bioconversion of Steroids in Immature Rat Testesin Vitro1

Bioconversion of Steroids in Immature Rat Testesin Vitro1

Rapid mechanisms of glucocorticoid signaling in the Leydig cell☆

Methods for the Study of Gonadal Development

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