scholarly journals Subcellular distribution of Δ5-3 β-hydroxy steroid dehydrogenase in the granulosa cells of the domestic fowl (Gallus domesticus)

1979 ◽  
Vol 181 (3) ◽  
pp. 685-689 ◽  
Author(s):  
D G Armstrong

1. The distribution of 3 beta-hydroxy steroid dehydrogenase was examined in the subcellular fractions of granulosa cells collected from the ovary of the domestic fowl. 2. 3 beta-hydroxy steroid dehydrogenase activity was observed in the mitochondrial (4000g for 20min) and microsomal (105 000g for 120min) fractions. 3. Approximately three times more 3 beta-hydroxy steroid dehydrogenase activity was associated with the cytochrome oxidase activity (a mitochondrial marker enzyme) in anteovulatory-follicle granulosa cells than with that of the postovulatory follicle. 4. Comparison of the latent properties of mitochondrial 3 beta-hydroxy steroid dehydrogenase with those of cytochrome oxidase and isocitrate dehydrogenase indicated that 3 beta-hydroxy steroid dehydrogenase is located extramitochondrially. 5. This apparent distribution of 3 beta-hydroxy steroid dehydrogenase is explained on the basis that the mitochondrial activity is either an artefact caused by a redistribution in the subcellular location of the enzyme, occurring during homogenization, or by the existence of a functionally heterogeneous endoplasmic reticulum that yields particles of widely differing sedimentation properties.

1985 ◽  
Vol 106 (3) ◽  
pp. 269-273 ◽  
Author(s):  
D. G. Armstrong

ABSTRACT The object of this study was to examine changes in the activity of granulosa 3β-hydroxy-Δ5-steroid dehydrogenase during the ovulatory cycle of the domestic fowl. The enzyme activity in granulosa tissue from the largest follicle increased significantly during the period 8–14 h before an expected ovulation. The increase in activity occurs before the preovulatory surge of LH and near the time of lights off. During the 4–8 h period before an ovulation, i.e. the time of maximal plasma LH concentrations, 3β-hydroxy-Δ5-steroid dehydrogenase activity decreased in granulosa tissue from the largest follicle. This observation is explained by proposing that the enzyme is inhibited by the large amounts of progesterone found in the tissue at this time. The results indicate that important biochemical changes are taking place within granulosa tissue of the largest ovarian follicle before the preovulatory LH surge. J. Endocr. (1985) 106, 269–273


Reproduction ◽  
1978 ◽  
Vol 52 (2) ◽  
pp. 227-229 ◽  
Author(s):  
A. B. Gilbert ◽  
M. F. Davidson ◽  
J. W. Wells

1965 ◽  
Vol 48 (3) ◽  
pp. 429-438 ◽  
Author(s):  
A. H. Baillie ◽  
M. Niemi ◽  
M. Ikonen

ABSTRACT Sections of testes from nine human foetuses ranging in crown-rump length from 3.0 to 18.3 cm were incubated to determine 3β-hydroxy-steroid dehydrogenase activity histochemically with the following steroids: 3β-hydroxy-pregn-5-en-20-one (pregnenolong). 3β,17α-dihydroxy-pregn-5-en-20-one (17α-hydroxypregnenolone). 3β-hydroxy-androst-5-en-17-one (DHA). 3β,17β-dihydroxy-androst-5-ene (androstenediol). 3β-sulphoxy-pregn-5-en-20-one (pregnenolone sulphate). 3β-sulphoxy-1 7α-hydroxy-pregn-5-en-20-one (17α-hydroxy-pregnenolone sulphate) 3β-sulphoxy-androst-5-en-17-one (DHAsulphate). 3β-hydroxy-5α-androstan-17-one (epiandrosterone). Pregnenolone and DHA gave a colour reaction in the interstitium of all testes studied. 17α-hydroxypregnenolone was utilised by testes from foetuses of C-R length 8.8 cm and over, androstenediol by testes from foetuses of C-R length 6.1 cm and over. These facts are thought to support the concept of separate substrate-specific 3β-hydroxysteroid dehydrogenases in the testis. Pregnenolone sulphate was used by the interstitial cells of all testes studied but gave a stronger reaction than the free steroid. 17α-hydroxy-pregnenolone sulphate was used by all foetal testes surveyed. DHA sulphate was not well used by the interstitial cells. The utilisation of steroid sulphates in a different manner from the free steroids in this histochemical system may mean that the presence of a sulphate group affects enzyme-substrate binding or that a steroid sulphatase is involved. Intense formazan deposition followed incubation with epiandrosterone in all testes studied. This seems to imply that a δ5 configuration is not necessary for enzyme-substrate binding.


2006 ◽  
Vol 20 (4) ◽  
pp. 458-463 ◽  
Author(s):  
H. Malekinejad ◽  
HTA.Van Tol ◽  
B. Colenbrander ◽  
J. Fink-Gremmels

1982 ◽  
Vol 93 (3) ◽  
pp. 415-421 ◽  
Author(s):  
D. G. Armstrong

The total and specific activity of 3β-hydroxy-Δ5-steroid dehydrogenase, isocitrate dehydrogenase (NADP+) and glucose-6-phosphate dehydrogenase were measured in ovarian follicles from the domestic fowl. The enzymes were assayed in the five largest yolk-filled follicles which were sampled twice during the ovulatory cycle, at 1 h and 16 h before an expected ovulation. The total and specific activity of granulosa enzymes increased throughout the hierarchy and reached a maximum in the largest follicle. The relative increase in 3β-hydroxy-Δ5-steroid dehydrogenase activity was greater than that of the other two enzymes examined. The total thecal 3β-hydroxy-Δ5-steroid dehydrogenase activity reached a maximum in the third and fourth largest follicles. Thereafter its activity decreased up to the time of ovulation. The activity of 3β-hydroxy-Δ5-steroid dehydrogenase and glucose-6-phosphate dehydrogenase in follicles collected 1 h before an ovulation were significantly less than the activity in corresponding follicles collected 16 h before an ovulation.


1983 ◽  
Vol 19 (4) ◽  
pp. 521-532 ◽  
Author(s):  
Z. M. SPUY ◽  
D. L. JONES ◽  
C. S. W. WRIGHT ◽  
B. PIURA ◽  
D. B. PAINTIN ◽  
...  

1975 ◽  
Vol 152 (3) ◽  
pp. 445-448 ◽  
Author(s):  
R G Rodway ◽  
N J Kuhn

Natural or early weaning of rat litters caused an increased activity of maternal luteal 20α-hydroxy steroid dehydrogenase and a decreased release of delta4-3-oxo steroids in vitro. 2. Compound CB-154 (2-bromo-α-ergocryptine) caused an increase of 20α-hydroxy steroid dehydrogenase activity in mid-lactation but not in early lactation. 3. Prolaction did not prevent these increases in enzyme activity.


1972 ◽  
Vol 127 (4) ◽  
pp. 649-659 ◽  
Author(s):  
E. Mulder ◽  
G. J. M. Lamers-Stahlhofen ◽  
H. J. Van Der Molen

1. The 17β-hydroxy steroid dehydrogenase was solubilized during haemolysis of erythrocytes and was isolated from the membrane-free haemolysate. Membrane preparations isolated in different ways did not contain 17β-hydroxy steroid dehydrogenase activity. The 17β-hydroxy steroid dehydrogenase activity in the haemolysate was concentrated by repeated ammonium sulphate precipitation and gel filtration on Sephadex G-150. The 17β-hydroxy steroid dehydrogenase activity of the purified preparation per unit weight of protein was 350–3000 times higher than the activity of the crude erythrocyte haemolysate. The 20α-hydroxy steroid dehydrogenase activity was lost during this purification procedure. 2. The 17β-hydroxy steroid dehydrogenase was NADP-dependent and had a pH optimum for conversion of testosterone between 8.5 and 10. For the molecular weight of the enzyme a value of 64000 was calculated from Sephadex chromatography results. 3. p-Chloromercuribenzoate inhibited the enzymic activity. The oxidative activity of the enzyme for the 17β-hydroxyl group was only partly inhibited when a large excess of 17-oxo steroids was added. The catalysing activity of the enzyme was influenced by the NADP+/NADPH ratio. The oxidation of the 17β-hydroxyl group in the presence of NADP+ proceeded faster than the reduction of the 17-oxo group with NADPH. When both reduced and oxidized cofactors were present the oxidation of the 17β-hydroxyl group was inhibited to a considerable extent. 4. The enzyme had a broad substrate specificity and not only catalysed the conversion of androstanes with a 17β-hydroxyl group, or 17-oxo group, but also the conversion oestradiol⇆oestrone. In addition the steroid conjugates dehydroepiandrosterone sulphate and oestrone sulphate were also converted. There were no indications that more than one 17β-hydroxy steroid dehydrogenase was present in the partially purified preparation.


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