ALTERATION OF 3β-HYDROXYSTEROID DEHYDROGENASE ACTIVITY IN RAT OVARIES DURING THE OESTROUS CYCLE

1974 ◽  
Vol 60 (3) ◽  
pp. 441-443 ◽  
Author(s):  
A. M. GAWIENOWSKI ◽  
J. N. CLARK ◽  
C. N. SRINIVASAN
Keyword(s):  
Enzyme Activity ◽  
Dehydrogenase Activity ◽  
Hydroxysteroid Dehydrogenase ◽  
Oestrous Cycle

SUMMARY The activity of 3β-hydroxysteroid dehydrogenase has been determined during various stages of the oestrous cycle in rats. The enzyme activity was high during pro-oestrus and oestrus but low during dioestrus I and II.

THE INFLUENCE OF HAEMOGLOBIN-S AND G6PD DEFICIENCY ON THE ACTIVITY OF THE 17β-HYDROXYSTEROID DEHYDROGENASE OF INTACT HUMAN ERYTHROCYTES

1974 ◽  
Vol 75 (4) ◽  
pp. 793-800
Author(s):  
A. O. Sogbesan ◽  
O. A. Dada ◽  
B. Kwaku Adadevoh
Keyword(s):  
Enzyme Activity ◽  
Dehydrogenase Activity ◽  
Sex Steroids ◽  
G6pd Deficiency ◽  
Incubation Medium ◽  
Hydroxysteroid Dehydrogenase ◽  
G6pd Activity ◽  
Reverse Transformation ◽  
Oxidative Transformation ◽  
Haemoglobin S

ABSTRACT The 17β-hydroxysteroid dehydrogenase activity in intact erythrocytes of Nigerian patients, in particular with regard to haemoglobin genotypes and G6PD* activity was studied. The G6PD activity of the erythrocyte did not affect the oxidative transformation of testosterone to androstenedione and of oestradiol to oestrone. The reduction (reverse transformation) was inhibited in G6PD-deficient erythrocytes but this inhibition was offset by the addition of 0.025 m glucose to the incubation medium. The per cent oxidation transformation of testosterone was higher in Hb-AA than in Hb-SS erythrocytes. It is suggested that the differences may be a result of either lower enzyme activity in the Hb-SS erythrocytes or of differences in the uptake and possibly binding of sex steroids by intact Hb-SS and Hb-AA erythrocytes.

scholarly journals A HISTOCHEMICAL METHOD FOR THE DEMONSTRATION OF 20α-HYDROXYSTEROID DEHYDROGENASE ACTIVITY IN RAT OVARIES

1964 ◽  
Vol 12 (9) ◽  
pp. 670-673 ◽  
Author(s):  
KÁROLY BALOGH
Keyword(s):  
Enzyme Activity ◽  
Corpus Luteum ◽  
Dehydrogenase Activity ◽  
Present Method ◽  
Hydroxysteroid Dehydrogenase ◽  
Microscopic Level ◽  
Corpora Lutea ◽  
Endocrine Glands ◽  
Progesterone Metabolism ◽  
Rat Ovary

20α-Hydroxysteroid dehydrogenase activity was localized histochemically in the corpus luteum of the rat by using Nitro-BT as an indicator. Intensive enzyme activity was obseryed in the corpus luteum cells, especially during involution. The placenta and corpora lutea of pregnancy failed to reveal enzyme activity during the last week of gravidity. Other tissues, including endocrine glands, liver and kidneys were also negative. The Present method offers a possibility to identify the sites of progesterone metabolism in the rat ovary at the microscopic level.

Purification and Properties of the Soluble 17β-Hydroxysteroid Dehydrogenase of Rabbit Uterus

1979 ◽  
Vol 34 (9-10) ◽  
pp. 726-737 ◽  
Author(s):  
Kunhard Pollow ◽  
Walter Eiger ◽  
Herrmann Heßlinger ◽  
Barbara Pollow
Keyword(s):  
Enzyme Activity ◽  
Dehydrogenase Activity ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Hydroxysteroid Dehydrogenase ◽  
Maximal Velocity ◽  
Ammonium Sulfate Precipitation ◽  
Ph Optimum ◽  
Mobility Data ◽  
Purification And Properties

Abstract 17 β-Hydroxysteroid dehydrogenase activity towards estradiol-17 β has been demonstrated in the 105,000 X g supernatant of rabbit uterus. Hydroxylapatite chromatography of the enzyme activity isolated by ammonium sulfate precipitation, gel filtration and DEAE-cellulose chromato­graphy yielded a single 17 β-hydroxysteroid dehydrogenase activity. Further purification of the enzyme preparation by isoelectric focusing resulted in multiple peaks of activity. The molecular weight or the enzyme, calculated from mobility data on Sephadex gel, is approximately 64,000. Some properties of partially purified 17 β-hydroxysteroid dehydrogenase activity have been studied. Estradiol-17 β reacts at a faster rate than testosterone. The Km for estradiol is 4.16X 10-5 mol/1 for the NAD-linked enzyme activity and 4.37 X 10-5 mol/1 when NADP as cofactor was used. The ratio of the maximal velocity for NADP to that for NAD was 1.42. The pH-optimum for estradiol appears between 9.5 and 10.5 and for estrone between 5.5 and 6.5. The enzyme appears to be of the sulfhydryl type.

INCREASED RATIO OF 5α-REDUCTASE: 3α(β)-HYDROXYSTEROID DEHYDROGENASE ACTIVITIES IN THE HYPERPLASTIC HUMAN PROSTATE

1979 ◽  
Vol 80 (3) ◽  
pp. 289-301 ◽  
Author(s):  
NICHOLAS BRUCHOVSKY ◽  
GARY LIESKOVSKY
Keyword(s):  
Enzyme Activity ◽  
Dehydrogenase Activity ◽  
Reductase Activity ◽  
Hydroxysteroid Dehydrogenase ◽  
Normal Prostate ◽  
Tissue Protein ◽  
Abnormal Accumulation ◽  
Hyperplastic Tissue ◽  
The Mean ◽  
Generating System

The activities of 5α-reductase and 3α(β)-hydroxysteroid dehydrogenase were assayed in homogenates of eight normal, 21 hyperplastic and four carcinomatous human prostates. Samples consisting of 300–500 μg tissue protein in Tris buffer, pH 7·0, were incubated at 37 °C for 30 min in the presence of 50 nm-[3H]androgen and an NADPH-generating system started with 5 × 10−4 m-NADP. The yield of 5α- and 3α-reduced metabolites, as established by using t.l.c. and g.l.c., gave an estimate of enzyme activity. The formation of metabolites denoting 5α-reductase activity in normal, hyperplastic and carcinomatous tissue respectively was 28·8 ± 47 (s.e.m.), 76·8 ± 8·9 and 3·5 ± 0·7 pmol 30 min−1 mg protein−1; similarly, that denoting 3α(β)-hydroxysteroid dehydrogenase activity was 69·3 ± 6·7, 46·6 ± 5·7 and 38·8 ± 22·1 pmol 30 min−1 mg protein−1. In all normal prostates 5α-reductase activity was lower than 3α(β)-hydroxysteroid dehydrogenase activity. Conversely, in 18 out of 21 hyperplastic prostates, 5α-reductase activity was higher than 3α(β)-hydroxysteroid dehydrogenase activity. The effect of the increase in 5α-reductase activity without a compensatory change in 3α(β)-hydroxysteroid dehydrogenase activity was to alter the mean ratio between 5α-reductase and 3α(β)-hydroxysteroid dehydrogenase activities from 0·47 ± 0·11 in the normal prostate to 1·84 ± 0·19 in hyperplastic tissue. It is inferred that this change may predispose the hyperplastic prostate to asymmetrical rates of androgen metabolism and thereby contribute to the abnormal accumulation of dihydrotestosterone.

11β-Hydroxysteroid dehydrogenase in the rat placenta: developmental changes and the effects of altered glucocorticoid exposure

1994 ◽  
Vol 143 (3) ◽  
pp. 505-513 ◽  
Author(s):  
P J Burton ◽  
B J Waddell
Keyword(s):  
Enzyme Activity ◽  
Dehydrogenase Activity ◽  
Placental Tissue ◽  
Hydroxysteroid Dehydrogenase ◽  
Developmental Changes ◽  
Hypothalamic Pituitary Adrenal ◽  
Dexamethasone Acetate ◽  
Near Term ◽  
Percentage Conversion ◽  
Made In

Abstract The enzyme 11β-hydroxysteroid dehydrogenase (11β-HSD) catalyses the interconversion of corticosterone, the major glucocorticoid of the rat, and the biologically-inactive 11-dehydrocorticosterone. In the placenta, 11β-HSD is thought to regulate glucocorticoid transport between maternal and fetal compartments, and may also affect the local action of glucocorticoids. The present study assessed whether 11β-dehydrogenase (corticosterone to 11-dehydrocorticosterone) and 11-oxoreductase (11-dehydrocorticosterone to corticosterone) activities are both present in rat placenta, and whether these activities change with advancing pregnancy. Enzyme activity was estimated on days 16, 19 and 22 of pregnancy (term=day 23) in placental fragments incubated for 6 h with either [3H]corticosterone or [3H] 11-dehydrocorticosterone. The percentage conversion of these substrates to [3H] 11-dehydrocorticosterone and [3H] corticosterone, respectively, were determined at the end of the incubation. Both 11-oxoreductase and 11β-dehydrogenase activities were clearly evident in placental tissue fragments, and while 11-oxoreductase activity declined with advancing pregnancy (P<0·01), 11β-dehydrogenase activity increased (P<0·01). Thus, 11-oxoreductase exceeded (P<0·05) 11β-dehydrogenase at day 16, but thereafter activities were similar. These changes do not appear to be glucocorticoid-induced, since pretreatment of rats with either metyrapone or dexamethasone acetate from day 15 of pregnancy did not affect placental 11β-HSD on day 22. To allow comparison with earlier studies, estimates of 11β-HSD were also made in placental homogenates at each stage of pregnancy. In contrast to observations in placental fragments, 11β-dehydrogenase was always the dominant reaction in homogenates, presumably due to the loss of 11-oxoreductase activity following tissue homogenisation. These data demonstrate that net 11β-dehydrogenase activity in the rat placenta increases towards term, thereby increasing the capacity for placental inactivation of active glucocorticoid. This pattern of 11β-HSD is consistent with reduced transfer of active glucocorticoid between the mother and fetus near term, and thus should promote independence of their hypothalamic-pituitary-adrenal axes. Journal of Endocrinology (1994) 143, 505–513

Relationship between glucose and 20α-hydroxysteroid dehydrogenase in fetal sheep erythrocytes

1984 ◽  
Vol 101 (2) ◽  
pp. 131-139
Author(s):  
C. D. Nancarrow ◽  
P. J. Connell ◽  
D. Stevens
Keyword(s):  
Enzyme Activity ◽  
Dehydrogenase Activity ◽  
Plasma Glucose ◽  
Whole Blood ◽  
Hydroxysteroid Dehydrogenase ◽  
Adult Type ◽  
Fetal Sheep ◽  
Sheep Erythrocytes ◽  
Fetal Plasma ◽  
Rate Of Reaction

ABSTRACT We have examined whether glucose supply to fetal sheep erythrocytes limits the rate of 20α-reduction of progesterone in blood and as such is associated with the progressive loss of 20α-hydroxysteroid dehydrogenase activity which has been observed from 30 days before term. Enzyme activity in erythrocytes depleted of glucose by washing was regained in the presence of at least 0·167 mmol glucose/l. The cofactor NADPH was necessary to support the reaction in lysed cells. Addition of glucose to whole blood diluted 20-fold for assay of 20α-hydroxysteroid dehydrogenase did not increase the rate of reaction. Infusion of dextrose to increase fetal plasma glucose concentrations had no effect on 20α-hydroxysteroid dehydrogenase activity. Over the period from 114 to 137 days of gestation, both dextrose- and saline-infused fetuses showed a decline in enzyme activity from a combined mean of 1·45 ± 0·21 (s.e.m.) to a mean of 0·78 ± 0·18 μmol/ml erythrocytes per h. Fetal leucocytes did not contribute significantly to the activity of 20α-hydroxysteroid dehydrogenase in whole blood. The rate of 20α-reduction of progesterone in the blood of eight fetuses with indwelling carotid catheters declined from 2·31 ± 0·09 μmol/ml erythrocytes per h at 90–95 days of gestation to 0·73 ± 0·04 μmol/ml per h at 141–145 days. However, a consistent decline was only observed after 116–120 days. The apparent equilibrium position for progesterone reduction to 20α-dihydroprogesterone varied between 83·9 ± 1·8 and 65·7 ± 4·2%. Thus, it appears that the decline in 20α-hydroxysteroid dehydrogenase activity which occurs in whole blood of sheep fetuses during the last 30 days of gestation is due to dilution of the fetal erythrocytes with adult-type erythrocytes rather than development of limiting concentrations of plasma glucose. J. Endocr. (1984) 101, 131–139

CORTISOL UTILIZATION BY SALIVARY GLAND, KIDNEY AND ADRENAL CORTEX

1970 ◽  
Vol 47 (4) ◽  
pp. 511-515 ◽  
Author(s):  
M. M. FERGUSON ◽  
J. B. GLEN ◽  
D. K. MASON
Keyword(s):  
Enzyme Activity ◽  
Sex Differences ◽  
Salivary Gland ◽  
Salivary Glands ◽  
Dehydrogenase Activity ◽  
Adrenal Cortex ◽  
Hydroxysteroid Dehydrogenase ◽  
Histochemical Technique ◽  
Hydroxysteroid Dehydrogenases ◽  
Convoluted Tubules

SUMMARY Cortisol utilization by salivary glands, kidneys and adrenals of various mammals has been compared by using a standard histochemical technique for the demonstration of hydroxysteroid dehydrogenases. 11β-Hydroxysteroid dehydrogenase activity was localized in salivary gland ducts, renal collecting and convoluted tubules and in the adrenal cortex of some species. There was no obvious relationship between the levels of enzyme activity in the salivary glands, kidneys and adrenals. Neither was the presence of 11β-hydroxysteroid dehydrogenase in salivary glands particularly associated with mucous or serous secretion, nor were sex differences in levels of activity evident.

EFFECTS OF OESTRADIOL ON STEROID DEHYDROGENASE ACTIVITIES IN RAT CORPORA LUTEA

1980 ◽  
Vol 84 (3) ◽  
pp. 391-395 ◽  
Author(s):  
R. G. RODWAY ◽  
I. ROTHCHILD
Keyword(s):  
Enzyme Activity ◽  
Dehydrogenase Activity ◽  
Hydroxysteroid Dehydrogenase ◽  
Corpora Lutea ◽  
Pregnant Rat ◽  
Oestradiol Treatment ◽  
Rapid Induction ◽  
Progesterone Secretion ◽  
Luteal Tissue ◽  
Steroid Dehydrogenase

The activities of 20α-hydroxysteroid dehydrogenase and 3β-hydroxysteroid dehydrogenase in rat corpora lutea during the second half of pregnancy were measured. In luteal tissue of the intact pregnant rat, 20α-hydroxysteroid dehydrogenase activity was undetectable between days 12 and 18 of pregnancy but appeared slowly after hypophysectomy and hysterectomy on day 12. Treatment of the hypophysectomized and hysterectomized animal with oestradiol delayed this increase until day 17, at which time a rapid induction of this enzyme occurred. In the normal pregnant rat mean luteal 3β-hydroxysteriod dehydrogenase activity increased between days 12 and 18 (P <0·05, Student's t-test) but fell rapidly after hypophysectomy and hysterectomy on day 12. Oestradiol treatment prevented this fall in activity and enzyme activity was not distinguishable from that of the intact rat. Progesterone secretion correlated well with the activities of these two enzymes in the three conditions examined.

ACUTE ENZYME HISTOCHEMICAL CHANGES IN THE ZONA GLOMERULOSA OF THE RAT ADRENAL CORTEX

1968 ◽  
Vol 59 (3) ◽  
pp. 508-518
Author(s):  
J. D. Elema ◽  
M. J. Hardonk ◽  
Joh, Koudstaal ◽  
A. Arends
Keyword(s):  
Peritoneal Dialysis ◽  
Succinate Dehydrogenase ◽  
Dehydrogenase Activity ◽  
Adrenal Cortex ◽  
Isocitrate Dehydrogenase ◽  
Hydroxysteroid Dehydrogenase ◽  
Zona Glomerulosa ◽  
Acute Changes ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Histochemical Changes

ABSTRACT Acute changes in glucose-6-phosphate dehydrogenase and isocitrate dehydrogenase activity in the zona glomerulosa of the rat adrenal cortex were induced by peritoneal dialysis with 5 % glucose. Although less clear, the activity of 3β-ol-hydroxysteroid dehydrogenase also seemed to increase as well. No changes were seen in the activity of succinate dehydrogenase. Dialysis with 0.9 % NaCl had no effect on any of the enzymes investigated. The possible significance of these observations is discussed.

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