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1.
Summary The histochemical distribution of various hydroxysteroid dehydrogenases in human, term, foetal membranes has been investigated using the tetrazolium dye, Nitro-B.T.The trophoblastic layer was the most active, showing 3-, 3-, 11-, 16- and 17-hydroxysteroid dehydrogenase activities, a pattern of activity similar to that of the placental villous trophoblast.The amniotic epithelium showed weak 3-, 3-, 16- and 17-hydroxysteroid dehydrogenase activity; weak 3- and 3-hydroxysteroid dehydrogenase activity was noted in the connective tissue layers.All activity demonstrated was N.A.D.-linked.  相似文献   

2.
Synopsis A study of the ultrastructural localization of 3-hydroxysteroid dehydrogenase (3-HSD), 11-hydroxysteroid dehydrogenase (11-HSD), glucose-6-phosphate dehydrogenase (G-6-PD), -hydroxybutyrate dehydrogenase (-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-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-HSD and 11-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 -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.  相似文献   

3.
Synopsis The presence of5-3-hydroxysteroid dehydrogenase, II-hydroxysteroid dehydrogenase, 17-hydroxysteroid dehydrogenase and glucose-6-phosphate dehydrogenase has been demonstrated histochemically in the adrenal gland of the rain quailCoturnix coromendalica, barn owlTyto alba, brown crakeAmaurornis akool and painted partidgeFrancholinus pictus. All these enzymes occurred in the inter-renal cells. No activity was observed in the chromaffin cells. It is suggested that the inter-renal cells of these four species of birds are capable of synthesizing both corticosteroids and sex steroids.  相似文献   

4.
The effect of estradiol, hydrocortisone and progesterone on 3,20-and 3,17-hydroxysteroid dehydrogenase (HSD) in mutants of Streptomyces hydrogenans was compared to the steroid response of the wild type. Mutants were defective in arginine biosynthesis and/or aerial mycelial formation and lacked both enzymes or only 17-HSD. Some 17-HSD mutants had lost the ability to be induced by estradiol, by progesterone or by both. Some 20-HSD mutants had lost the ability to be induced by hydrocortisone, by progesterone or by both. Non-inducibility of 17-and 20-HSD by progesterone was not co-ordinate. An additional study of the growth phase-dependent enzyme activity of the wild type after induction with estradiol, hydrocortisone and progesterone was performed.Non-standard abbreviations 17-HSD 3,17-Hydroxysteroid dehydrogenase (EC 1.1.1.51) - 20-HSD 3,20-hydroxysteroid dehydrogenase (EC 1.1.1.53) - AO acridine orange - EBr ethidium bromide - EMS ethyl methanesulfonate - MNNG N-methyl-N-nitro-N-nitrosoguanidine  相似文献   

5.
Summary A fungus identified as Cunninghamella blakesleeana (Lendner) can carry out 15-hydroxylation of lithocholic acid to a new bile acid (3,15-dihydroxy-5-cholanic acid). By optimizing the fermentation conditions, the amount of the product increased from 0.17 g/l to 1.2 g/l. Hydrophilicity measurements and in vitro cholesterol solubilization tests showed that 3, 15-dihydroxy-5-cholanic acid was as effective as ursodeoxycholic acid in cholesterol solubilization.Abbreviations LCA lithocholic acid (3-hydroxy-5-cholanic acid) - 3, 15-DHC (3, 15-dihydroxy-5-cholanic acid) - DMSO dimethyl sulfoxide - CHES 2-[N-cyclohexylamino]ethanesulfonic acid  相似文献   

6.
We studied the segregation of the genes for 3-hydroxy-C19/21-steroid dehydrogenase types I and II (3-HSD I and II) in a consanguineous family affected with 3-hydroxy-5-C27steroid dehydrogenase (3-OH-C27-SD) deficiency. The results show that the C27 and C19/21 steroid dehydrogenase activities are encoded by distinct genes that are not in genetic linkage. Further kindreds would assist in screening for linkage of 3-OH-C27-SD to other members of the 3-hydroxysteroid dehydrogenase gene family.  相似文献   

7.
Summary Cholic acid (3,7,12-trihydroxy-5-cholanoic acid) was completely and selectively transformed into 12-ketoursodeoxycholic acid (3,7-dihydroxy-12-oxo-5-cholanoic acid) by means of two consecutive enzymatic steps catalyzed, the first, by 7- and 12-hydroxysteroid dehydrogenase and, the second, by 7-hydroxysteroid dehydrogenase. Coenzyme regeneration was carried out with -ketoglutarate-glutamate dehydrogenase and glucose-glucose dehydrogenase, respectively.  相似文献   

8.
Summary Mouse, rat, hamster, guinea pig and sheep kidneys and foetal human, adult male and female human, mouse, rat, hamster and guinea pig livers were examined for hydroxysteroid dehydrogenase activity.3-Hydroxysteroids were utilised by all tissues, including neonatal mouse kidney, but the 5-configuration was a more suitable substrate than the corresponding 5-steroid. Both N.A.D. and N.A.D.P. were suitable cofactors.Only trace 3-hydroxysteroid dehydrogenase activity was demonstrable in renal tissue, however liver possessed a higher level of activity and lanosterol, a precurser of cholesterol, was an especially suitable substrate possibly indicating that the liver is capable of synthesising cholesterol.6-Hydroxyprogesterone was poorly utilized by renal and hepatic tissue and N.A.D. was found to be the only cofactor suitable for this reaction. All the tissues, possessed 11-hydroxysteroid dehydrogenase activity. In the kidney, this enzyme occurred in the collecting tubules. It was further noted that in mouse kidney 11-hydroxysteroid dehydrogenase was absent at birth but appeared within the first fourteen days. Activity with 11-hydroxysteroids was observed to be more prominent in the liver of male animals and this pattern was also found with 3-, 3-, 16- and 16-hydroxysteroids, all of which are confirmed by previous biochemical findings.Renal tissue was not capable of utilizing the 16-hydroxysteroid in contrast to liver which could use this substrate fairly well. 16- and 17-hydroxysteroid dehydrogenases were demonstrable in the livers of all species and in all kidneys. The 20-hydroxysteroid was only poorly utilized by hepatic tissue and not at all by renal tissue.Slight activity was demonstrable with 5- and 5-androstans as substrates in liver and the diformazan deposition was presumably due to the action of a steroid reductase.  相似文献   

9.
Sodium fluoride (NaF) administered orally to adult male rats at a dose level of 4.5 ppm and 9.0 ppm for 75 days caused significant decrease in the body weight, brain index and testicular index. A significant decrease in sperm count, sperm motility, sperm viability and sperm function (HOS positive) with increased sperm abnormalities was also observed in NaF-exposed male rats. The activity levels of testicular steroidogenic marker enzymes 3-hydroxysteroid dehydrogenase (3-HSD) and 17-hydroxysteroid dehydrogenase (17-HSD) were significantly decreased in NaF-treated rats indicating decreased steroidogenesis and in turn spermatogenesis in rats exposed to NaF.  相似文献   

10.
Synopsis The ovary of the domestic pigeon,Columba livia, has been assayed histochemically for the localization of 5-3-hydroxysteroid dehydrogenase (5-3-HSDH), 17-hydroxysteroid dehydrogenase (17-HSDH), 11-hydroxysteroid dehydrogenase (11-HSDH), glucose-6-phosphate dehydrogenase (G6P-DH) and NADH-diaphorase activities during different periods of the reproductive cycle. 5-3-HSDH, 17-HSDH, 11-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 5-3-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.  相似文献   

11.
Summary Parotid, submandibular and sublingual glands were removed from rats and investigated histochemically. Pyruvate oxidase, iso-citric dehydrogenase, -ketoglutarate oxidase, succinic dehydrogenase, malate dehydrogenase and furfuryl alcohol dehydrogenase activity were observed in the salivary ducts which may be interpreted as significant of high metabolic activity.The 11 -hydroxysteroid dehydrogenase in these ducts displayed marked substrate specificity utilizing 11-hydroxyandrostenedione and cortisol but not 11 -hydroxyoestrone or 11 -hydroxyprogesterone. The relationship between corticosteroids and salivary electrolyte concentrations is discussed.  相似文献   

12.
Synopsis Histochemical studies on the activity of 3-hydroxysteroid dehydrogenase (3-HSD) in the testes of adult chicken-pheasant hybrids and domestic fowl of similar age were carried out using dehydroepiandrosterone as the substrate. The reaction for 3-HSD was positive in the interstitial tissue and negative within seminiferous tubules of domestic fowl. In chicken-pheasant hybrids, a strong positive reaction for 3-HSD was observed in the interstitial tissue and within the seminiferous tubules suggesting that, in hybrid testes, both Leydig cells and cells of seminiferous tubules may be capable of steroid biosynthesis. Since the plasma testosterone levels in these birds were found to be extremely low, it is hypothesized that either the chicken-pheasant hybrids do not release testosterone in sufficient amounts in the circulation or the type of steroid produced by the 3HSD-positive cells may be different from testosterone that is required for the maintenance of normal fertility and the development of secondary sexual characteristics.  相似文献   

13.
Both in vitro and in vivo HgCl treatment demonstrated a remarkably high rate of progesterone synthesis accompanied by a low rate of conversion to 17-estradiol in the oocyte of Channa punctatus. On depuration, however, there was a reversal of the steroidogenic scenario with a low progesterone and high estradiol level. The accumulation of progesterone was positively correlated with the significant increase in 3-hydroxysteroid dehydrogenase activity in the Hg-treated fish. Thus, it was clear that at the early stage of intoxication Hg does play a role in the induction of 3-hydroxysteroid dehydrogenase in the oocyte of fish at the spawning stage. The induction of this enzyme was found to be mediated by specific binding of Hg to the plasma membrane Na-K-ATPase (B: 14 nmoles mg protein; K 1.14 x 108 moles) and increase in the specific messenger RNA translating 3-hydroxysteroid dehydrogenase. It is concluded that inorganic mercury is able to initiate translatable messenger RNA synthesis in fish oocyte at a low degree of intoxication.  相似文献   

14.
Four glycosidases were analyzed in 10 mm apical segments prepared from growing roots (15 mm) of Zea mays L. The pH optima were found to be 5.8 for -glucosidase, 4.4 for -galactosidase, 6.4 for -glucosidase and 6.0 for -galactosidase. The -glucosidase showed 4-fold higher activity than the -galactosidase. The distribution of the -glucosidase activity was signifcantly different from that of the -galactosidase, -glucosidase and -galactosidase.Abbreviations -Glu -glucosidase - -Gal -galactosidase - -Glu -glucosidase - -Gal -galactosidase  相似文献   

15.
Summary The effects of carp pituitary suspension (CPS) and 11-desoxycorticosterone-acetate (DOCA) on 3-hydroxysteroid dehydrogenase (3-HSD) and glucose-6-phosphate dehydrogenase (G6PD) activity in the ovary of Clarias lazera are described. Strong 3-HSD and G6PD activities are localized in the stroma, of both control and treated fish. A single CPS injection stimulates 3-HSD activity in the granulosa of postvitellogenic, maturing and postovulatory follicles, but DOCA has no such effect on the postvitellogenic and maturing follicles, and only stimulates a weak response in the postovulatory ones.  相似文献   

16.
Synopsis 3- and 17-hydroxysteroid dehydrogenase activities were studied histochemically in the male reproductive tract of the domestic fowl. 3-hydroxysteroid dehydrogenase was NAD+-linked and was capable of metabolizing the three substrates used, namely, pregnenolone, 17-hydroxypregnenolone and dehydroepiandrosterone. 17-hydroxysteroid dehydrogenase oxidized testosterone in the presence of NAD+ or NADP+. The pattern of distribution of formazan granules was essentially the same with all the substrates used, and they were located in the Leydig cells, seminiferous tubules and the lining epithelia of the entire excurrent duct system of the testis except the rete testis. The activity of both enzymes appeared to be highest in the ductuli efferentes and decreased distally along the tract. The evidence suggests that steroid synthesis may occur in the epithelial lining of the excurrent ducts as well as in the cells of the testis.  相似文献   

17.
    
A partially purified preparation of 1,3-fucosyltransferase(s) from human milk was used to [14C]fucosylate oligosac-charides containing Gal1-4GlcNAc units. Substitution ofN-acetyllactosamine at position 3 with a -linkedN-acetylglucosamine enhanced the reactivity of the acceptor, whereas similar substitution at position 6 was inhibitory. Thus, the trisaccharide GlcNAcl-6Gal1-4GlcNAc (5), the branched tetrasaccharide GlcNAc1-3(GlcNAc1-6)Gal1-4GlcNAc (11) and the triply branched decasaccharide GlcNAc1-3(GlcNAc1-6)Gall-4GlcNAc1-3[GlcNAc1-3(GlcNAc1-6)Gal1-4GlcNAc1-6]Gal1-4GlcNAc (26) gave remarkably poor yields of 1,3-fucosylated products in comparison to GlcNAc1-3Gal1-4GlcNAc (3). 1,4-Galactosyl derivatives of5 and11, however, gave good yields of 1,3-fucosylated products, but the fucosylation was restricted to the distalN-acetyllactosamine units of Gal1-4GlcNAc1-6Gal1-4GlcNAc (16), Gal1-4GlcNAc1-3(Gal1-4GlcNAc1-6)Gal1-4GlcNAc (18) and also in Gal1-3Gal1-4GlcNAc1-3(Gal1-3Gal1-4GlcNAc1-6)Gal1-4GlcNAc (22). Immobilized wheat germ agglutinin (WGA), possessing high affinity for16 [1], revealed no affinity for the fucosylated derivative Gal1-4(Fuc1-3)GlcNAc1-6Gal1-4GlcNAc (17). The isomeric heptasaccharides Gal1-4(Fuc1-3)GlcNAc1-3(Gal1-4GlcNAc1-6)Gal1-4GlcNAc (19) and Gal1-4GlcNAc1-3[Gal1-4(Fuc1-3)GlcNAc1-6]Gal1-4GlcNAc (20) were readily separated from each other on WGA-agarose, and so were the isomeric nonasaccharides Gal1-3Gal1-4(Fuc1-3)GlcNAc1-3(Gal1-3Gal1-4GlcNAc1-6)Gal1-4GlcNAc (23) and Gal1-3Gal1-4GlcNAc1-3[Gal1-3Gal1-4(Fuc1-3)GlcNAc1-6]Gal1-4GlcNAc (24).  相似文献   

18.
Summary Short-term ACTH treatment provoked a decrease in volume of the lipid-droplet compartment in rat zona glomerulosa cells, and a rise in plasma and intracellular concentrations of corticosterone and aldosterone. It enhanced activities of 3-hydroxysteroid dehydrogenase (3HSD), 11-hydroxylase (11OH) and 18-hydroxylase (18OH). Long-term ACTH administration produced a hypertrophy of the zona glomerulosa and its parenchymal cells, a result of the increase in volume of the smooth endoplasmic reticulum and the mitochondrial compartment. The surface area per cell of mitochondrial inner membranes increased; the tubular cristae were transformed into a homogeneous population of vesicles. The plasma and intracellular concentrations of corticosterone further increased, whereas those of aldosterone fell below basal levels (the aldosterone-escape phenomenon). The activities of 3HSD and 11OH were enhanced, that of 180H decreased. Therefore, ACTH stimulates zona glomerulosa growth and transforms parenchymal elements into zona fasciculata celltypes. Cyanoketone nullified acute ACTH effects on plasma and intracellular concentrations of corticosterone and aldosterone, but did not affect the activities of 11OH and 18OH. Chronic ACTH treatment produced similar results, although 18OH activity was not suppressed. The mechanism underlying the aldosterone-escape phenomenon may thus involve a rise in the intracellular concentration of corticosterone, caused by the enhanced synthesis and activation of 3HSD and 11OH.  相似文献   

19.
-N-Acetyl-d-hexosaminidase from Aspergillus oryzae catalysed the stereo- and regiospecific formation of the 6-O-benzylated disaccharide derivatives GalNAc1-3(6- OBn)Gal-SEt and GlcNAc1-3(6-OBn)Gal-SEt, which were obtained in transglycosylation reactions employing ethyl 6- O-benzyl-1-thio--d-galactopyranoside as acceptor. Preparative amounts of the chitobiose derivative GlcNAc1- 3GlcNAc-OPhNO2-p was prepared as well. - N-Acetyl-d-hexosaminidase from bovine testes catalysed the specific synthesis of GlcNAc1-3(6-OBn)GlcNH2-SEt and GalNAc1-3(6-OBn)GlcNH2-SEt, employing ethyl 2-amino-6-O-benzyl-2-deoxy-1-thio--d-glucopyranoside as acceptor. -d-Glucuronidase from E. coli was found to catalyse the formation of GlcA1-3(6-OBn)GlcNH2- SEt employing the same acceptor.  相似文献   

20.
Summary We applied qualitative cytochemical procedures to investigate and compare the distribution of 3-hydroxysteroid dehydrogenases (HSDH) in pro- and diestrus ovaries of sexually mature marmosets (Callithrix jacchus) using dehydroepiandrosterone or etiocholane-3-ol-17-one as the substrate. During proestrus dehydroepiandrosterone dehydrogenase (3-5-HSDH) activity was found in the theca of tertiary follicles and in atretic granulosa cells. In granulosa cells at advanced stages of degeneration, HSDH activity was distinctly higher than in thecal cells. The activity of etiocholane-3-ol-17-one dehydrogenase (3-5-HSDH) exhibited a gradient in preovulatory follicles, ranging from high levels in granulosa cells adjacent to the basement membrane to low levels in cells bordering on the antrum and in cumulus oophorus cells. During diestrus 3-5-HSDH activity was only detected in the corpora lutea; the level of 3-5-HSDH activity was unchanged in the theca of tertiary follicles and high in the cells of the corpora lutea. HSDH activity was no longer detectable in atretic granulosa cells using either dehydroepiandrosterone or etiocholane-3-ol-17-one as the substrate. comparison of the distribution of HSDH during proestrus and diestrus revealed that steroidogenesis in marmoset ovaries occurs in follicular elements during diestrus and almost exclusively in the corpora lutea during diestrus. From this phase-dependent localization, it is possible to detemine the stage of the estrous cycle. Furthermore, our findings indicate that the localization of HSDH is dependent on the conformational structure of the substrate used.  相似文献   

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