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1.
Organ culture of rat lateral prostate was performed in the presence of testosterone and cadmium. Maintenance of epithelial cells did not occur even in the presence of the androgen, but basal cells were stimulated and replaced original epithelium. Testosterone alone caused a partial differentiation of these basal cells. Cadmium alone was found to enter the epithelial and basal cells and subsequently cause necrosis. The metal was subcellularly located in the nucleus and within cytoplasmic organelles. Cadmium appears to compete with zinc in cultured lateral prostate and affects the differentiation and maintenance of the epithelial growth.  相似文献   

2.
Summary The fine structure of the secretory epithelial cells of rat's ventral prostate has been studied following organ culture. Culturing with either testosterone or insulin alone, and with the two hormones combined, were carried out to investigate how insulin modifies the action of testosterone on the maintenance of cellular integrity. After 4 days in hormone-free culture, the secretory epithelial cells showed signs of cellular atrophy and regression, involving loss of the apical microvilli, absence of the apical secretory vacuoles, atrophy of the Golgi apparatus, decrease in rough endoplasmic reticulum and the appearance of autophagic vacuoles. The presence in the medium of either testosterone or insulin alone, or combined, prevented cellular atrophy and regression. The best maintenance of cellular integrity was obtained in a culture containing both hormones. The effects of insulin was approximately equivalent to those of testosterone in the maintenance of cellular integrity.  相似文献   

3.
M Matsui  Y Kinuyama  M Hakozaki 《Steroids》1975,25(5):637-648
Following intraperitoneal injection of a mixture of testosterone-7-3-H-17-sulfate and testosterone-4-14-C into male and female rats with bile fistulas, biliary metabolites were separated and purified by a combination of column chromatography, enzymic hydrolysis or solvolysis of the conjugate fractions and identification of the liberated aglycones. The injected steroids were extensively metabolized and excreted predominantly in the bile. The major portion of the 3H was excreted in the disulfate fraction in both sexes. Solvolysis of the disulfate revealed the sex-specific aglycone pattern: 5alpha-Androstane-3beta,17beta-diol was the major metabolite in the male rat, whereas 5alpha-androstane-3alpha,17beta-diol and polar steroids were found in the female. In marked contrast, testosterone was metabolized in a different way than testosterone sulfate. 14-C radioactivity was distributed in monoglucosiduronate, monosulfate, and diconjugate fractions. Analysis of the aglycones showed that polar steroids were the main metabolites in the male. In the female, testosterone was metabolized to polar steroids, androsterone, and 5alpha-androstane-3alpha,17beta-diol.  相似文献   

4.
The strain of Absidia coerulea was used to investigate the transformations of testosterone, androstenedione, progesterone and testosterone derivatives with additional C1–C2 double bond and/or 17-methyl group. All the examined substrates were transformed, mainly hydroxylated. It was found that the position and stereochemistry of the introduced hydroxyl group, as well as the yield of products, depended on the structure of the substrate. The first three substrates (hormones) underwent hydroxylation at C-14, and additional hydroxylation at 7 was observed in progesterone. The presence of the double bond (C1–C2) in 1-dehydrotestosterone did not influence the position of hydroxylation, but the product with additional C14–C15 double bond (at the same site as hydroxylation) was formed. 17-Methyltestosterone was hydroxylated at the 7 position, and also the dehydrogenated product (at the same site, with C6–C7 double bond) was obtained. The testosterone derivative with both C1–C2 double bond and 17-methyl group underwent hydroxylation at the 7 or 11β position, and a little amount of 14, 15 epoxide was formed.  相似文献   

5.
Summary Organ cultures of rodent and human prostate glands have shown marked differences in their morphological response to testosterone. In this study, explants from 19 canine prostate glands were cultivated for a minimum of 9 days in Trowell’s T-8 medium. Groups of explants were exposed to media containing from 0.05 to 100 μm testosterone. While the higher testosterone levels (50 and 100 μm) markedly decreased explant viability, explants cultivated at lower levels (0.05 to 5 μm) appeared similar to control explants in testosterone-free Trowell’s T-8 medium. Atmospheric mixtures containing either 95% or 50% oxygen were equally effective. Shortly after the cultures were initiated, large amounts of secretory product were liberated into the lumen. After 9 or more days in vitro, glandular epithelium appeared cuboidal and never revealed the acid phosphatase-rich secretory granules seen in the preculture control. However, the epithelium exhibited an increase in alkaline phosphatase and lipid content following cultivation. This project was supported by contract N01-CP-33331, Carcinogenesis Program, Division of Cancer Cause and Prevention, National Cancer Institute, Bethesda, Maryland.  相似文献   

6.
Marked differences were seen between the metabolism of L-[3-14C] tryptophan and of [2-14C]serotonin by the intact chick pineal gland in organ culture. The major metabolite of tryptophan recovered by our procedures was melatonin, which accounted for about half the radioactivity recovered as metabolic products. In contrast, the principal product of serotonin metabolism recovered was hydroxyindoleacetic acid, and the yield of products derived through monoamine oxidase (EC 1.4.3.4) activity vastly exceeded that of melatonin. Metabolism of tryptophan yielded a much larger proportion of methlated metabolites among the products recovered than did metabolism of serotonin. However, the yield of methoxyindoleacetic acid from serotonin was greater than that from tryptophan. Serotonin formed endogenously and serotonin supplied exogenously appear to enter two or more largely distinct metabolic pools.  相似文献   

7.
Testosterone and ten of its metabolites were examined as inhibitors of butyrylcholinesterase. A significant enzyme inhibition activity (IC(50) = 1.55 microM) was observed for androst-4-en-3,7-dione. The kinetic parameters of butyrylcholinesterase inhibition were determined and molecular docking was carried out in order to develop a better understanding of the inhibitor-enzyme interactions. The results showed that the inhibition was non-competitive, stabilized mainly by hydrogen bonds and hydrophobic interactions between the inhibitor and butyrylcholinesterase.  相似文献   

8.
Testosterone and ten of its metabolites were examined as inhibitors of butyrylcholinesterase. A significant enzyme inhibition activity (IC50 = 1.55 μM) was observed for androst-4-en-3,7-dione. The kinetic parameters of butyrylcholinesterase inhibition were determined and molecular docking was carried out in order to develop a better understanding of the inhibitor-enzyme interactions. The results showed that the inhibition was non-competitive, stabilized mainly by hydrogen bonds and hydrophobic interactions between the inhibitor and butyrylcholinesterase.  相似文献   

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11.
Organ explants from the canine prostate with and without methylprednisolone pretreatment were cultivated for ten days in Trowell's T-8 medium or medium supplemented with testosterone and/or vitamin A. Upon termination of the experiments, explants were fixed and examined histologically. All glands from the most central section of each explant were graded according to epithelial type, and from these grades the proportion of acini with maintained columnar cells was calculated for each explant. Stromal cellular maintenance was also estimated. While a small proportion of explants from the vitamin-treated and methylprednisolone-pretreated groups showed epithelial maintenance, a combination of these treatments significantly increased such maintenance. Stromal maintenance was enhanced with methylprednisolone pretreatment but not by vitamin A. These results are in accord with the hypothesis that methylprednisolone acts to stabilize the lysosomal membrane, thus protecting tissue against the effects of ischemic shock. In protected explants vitamin A is able to maintain a columnar glandular epithelium. In a subsequent experiment a series of linoleic acid dosages was tested in the presence or absence of vitamin A. In neither case was this fatty acid of value in improving epithelial or stromal maintenance.  相似文献   

12.
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14.
M Matsui  Y Kinuyama  M Hakozaki 《Steroids》1974,24(4):557-573
A mixture of testosterone-4-14C and testosterone-1,2-3H-17-glucosiduronate was intraperitoneally administered into male and female rats with bile fistulas. Biliary metabolites were separated and purififd by a combination of column chromatography, enzymic hydrolysis or solvolysis of the conjugate fractions and identification of the liberated aglycones. The injected steroids were extensively metabolized and excreted predominantly in the blue. 5β-Androstane-3α, 17β-diol was found principally in monoglucosiduronate fraction and was produced preferentially from the injected conjugate in both sexes. Very marked sex differences from the injected conjugate in both sexes. Very marked sex differences were observed in the following metabolites: Androsterone was present only in the female as monoglucosidironate, which was preferentially derived from testosterone. 5α-Androstane-3α,17β-diol was identified in both monoglucosiduronate and diconjugate fractions of the female, which was formed significanrly more from the conjugate than testosterone. These findings provide evidence that testosterone glucosiduronate could be converted directly into 5α-steroids as well as 5β-ones invivo. In marked contrast, the major portion of testosterone was metabolized to polar steroids in the male.  相似文献   

15.
All-trans-[3H]retinyl acetate has been shown to be metabolized to all-trans-[3H]retinoic acid in a target tissue of vitamin A action, the hamster trachea in organ culture. That the compound produced is indeed all-trans-retinoic acid is demonstrated by chromatography of the biosynthetically produced retinoic acid with synthetic all-trans-retinoic acid in two different high-pressure liquid chromatographic systems, either as the free acids in a reverse-phase system or as the methyl esters in a normal-phase system. The all-trans-[3H]retinoic acid was also found in the tracheal epithelium and cartilage as well as in the medium. In addition the tracheal tissue also contained retinyl palmitate and other esters. Finally, further in vitro metabolism of [3H]retinyl acetate paralleled the metabolism of [3C]retinoic acid suggesting that these two compounds are being metabolized through similar pathways.  相似文献   

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18.
P Ofner  M R Nadeau  R L Vena  I Leav 《Steroids》1992,57(2):50-55
Since dorsolateral but not ventral prostate undergoes estrogen-induced dysplasia in the androgen-supported Noble rat in 16 weeks, we studied estrogen metabolism by these tissues from untreated and sex hormone-implanted animals. We incubated 8.5 nM [6,7-3H]-labeled estradiol (E2) and estrone (E1) for 21 hours in serum-free, prostate-lobe cultures and 8.5 nM [2-3H]E2 with explants from untreated rats and animals treated with testosterone, 5 alpha-dihydrotestosterone, or E2 plus testosterone. Untreated rat ventral prostate metabolized 3.7 times as much E2 to E1 as dorsolateral prostate, whereas the latter tissue converted 2.5 times as much E1 to E2 as the former. After dorsolateral prostate culture with 8.5 nM [6,7-3H]-labeled E2 or E1, 0.6 M KCl-extracted, Sephadex G25-excluded nuclear protein bound preponderantly E2, whereas the counterpart nuclear protein fraction from ventral prostate explants incubated with E2 bound substrate and E1 almost equally. The combination sex hormone treatment decreased E2 metabolism and increased its uptake by the dysplastic dorsolateral prostate. Implantation of 5 alpha-dihydrotestosterone, but not of testosterone, also decreased E2 metabolism to E1 by dorsolateral prostate cultures. Treatments with E2 plus testosterone and with 5 alpha-dihydrotestosterone changed E2 uptake/E1 retention in dorsolateral prostate explants from 2.4 to 7.4 and 8.5, respectively. C-2 tritium release marking the 2,3-catechol estrogen pathway was greater for ventral than dorsolateral prostate, but was unaffected by the sex hormone treatments.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

19.
20.
Steroid metabolism in hepatoma tissue culture (HTC) cells derived from a male rat was investigated. Steroids in ethanol were incubated with the cells for various lengths of time. Volume of ethanol never exceeded 1% of incubation volume. Thin-layer and paper chromatography were used. Incubation was with tritiated steroids. It was demonstrated that testosterone as well as dihydrotestosterone is transformed. The main enzyme activities detected were 5alpha-reduction and 3alpha-, 3beta, and 17beta-hydroxysteroid dehydrogenation. The pattern of metabolism was reproducible and varied with time, substrate concentration, and number of cells incubated. Some steroids interfered with androgen metabolism. 17beta-estradiol, 17-epitestosterone, and progesterone competed for the 17beta-hydroxyprogesterone dehydrogenase. it is concluded that 3beta and 17beta reduction in the HTC cells may be catalyzed by the same enzyme which might differ considerably from the 3beta-hydroxysteroid dehydrogenase assayed in intact liver cells. A hepatoma derived from a female rat also produced considerable amounts of 3beta-derivatives of testosterone.  相似文献   

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