scholarly journals Functional Significance of Selective Expression of ERα and ERβ in Mammary Gland Organ Culture

2021 ◽  
Vol 22 (23) ◽  
pp. 13151
Author(s):  
Rajendra G. Mehta
Keyword(s):  
Organ Culture ◽  
Functional Significance ◽  
Precancerous Lesions ◽  
Mammary Glands ◽  
Short Exposure ◽  
Preneoplastic Lesions ◽  
Organ Cultures ◽  
Regulated Gene Expression ◽  
Microarray Analyses ◽  
Map Kinase Pathways

Thoracic pair of mammary glands from steroid hormone-pretreated mice respond to hormones structurally and functionally in organ culture. A short exposure of glands for 24 h to 7,12 Dimethylbenz(a)anthracene (DMBA) during a 24-day culture period induced alveolar or ductal lesions. Methods: To differentiate the functional significance of ERα and ERβ, we employed estrogen receptor (ER) knockout mice. We compared the effects of DMBA on the development of preneoplastic lesions in the glands in the absence of ERα (αERKO) and ERβ (βERKO) using an MMOC protocol. Glands were also subjected to microarray analyses. We showed that estradiol can be replaced by EGF for pretreatment of mice. The carcinogen-induced lesions developed under both steroids and EGF pretreatment protocols. The glands from αERKO did not develop any lesions, whereas in βERKO mice in which ERα is intact, mammary alveolar lesions developed. Comparison of microarrays of control, αERKO and βERKO mice showed that ERα was largely responsible for proliferation and the MAP kinase pathways, whereas ERβ regulated steroid metabolism-related genes. The results indicate that ERα is essential for the development of precancerous lesions. Both subtypes, ERα and Erβ, differentially regulated gene expression in mammary glands in organ cultures.

The Culture in vitro of Urogenital Organs of Pleurodeles waltlii

Development ◽  
1962 ◽  
Vol 10 (4) ◽  
pp. 465-470
Author(s):  
Charles L. Foote ◽  
Florence M. Foote
Keyword(s):  
Organ Culture ◽  
Germ Cells ◽  
Culture Medium ◽  
Developmental Stages ◽  
Rana Catesbeiana ◽  
Sex Differentiation ◽  
Organ Cultures ◽  
Tissue And Organ Culture ◽  
Pleurodeles Waltlii

Earlier reports (Foote & Foote, 1958a, b, 1959) describe growth and maintenance in vitro of larval organs, particularly gonads, of Rana catesbeiana and Xenopus laevis. Immature germ cells of both testes and ovaries are well maintained in vitro, especially if the culture medium is supplemented with watersoluble sex-hormonal substances, although germ cells in process of maturation become necrotic. Recently some urogenital organs from the salamander, Pleurodeles waltlii, have been grown in vitro. Tissues and organs from this amphibian might prove to be more suitable for tissue and organ culture investigations than those of Anurans. Animals at three different ages were used in this study: recently hatched larvae, metamorphosing animals, and adults. To determine whether sex differentiation would occur in vitro, trunk portions of young larvae of Pleurodeles waltlii of developmental stages 37–38 (Gallien & Durocher, 1957) were placed in organ cultures.

Synthesis of taurocholate by rat fetal liver in organ culture: effects of cortisol in vitro.

1979 ◽  
Vol 237 (2) ◽  
pp. E177 ◽  
Author(s):  
T O Graham ◽  
D H Van Thiel ◽  
J M Little ◽  
R Lester
Keyword(s):  
Organ Culture ◽  
Dose Response ◽  
Incubation Medium ◽  
Response Pattern ◽  
Fetal Liver ◽  
Dry Weight ◽  
Organ Cultures ◽  
In Vitro Incubation ◽  
Culture Effects

Taurocholate production by fetal hepatic organ cultures was measured by radioimmunoassay. Taurocholate production was maximal on day 1 of in vitro incubation, but was demonstrable in organ cultures maintained for periods up to 15 days. Explants obtained from fetuses of 18 gestational days of age produced only 82 pmol taurocholate per milligram dry weight of tissue during the first 24 h of incubation. Explants obtained from fetuses 21 gestational days of age produced 1,043 pmol taurocholate per milligram dry weight. The presence of cortisol (2.0 X 10(-6) M) in the incubation medium increased synthesis of taurocholate by rat fetal liver in which total taurocholate rose 50-fold above control after 120 h of incubation. In increasing concentrations from 2.0 X 10(-9) M to 2.0 X 10(-7) M, cortisol produced an incremental rise in taurocholate. However, additional increases in cortisol dose failed to provide further stimulation, and taurocholate production was inhibited by cortisol concentrations of 2.0 X 10(-5) M. The results provide further validation for the technique of fetal hepatic organ culture. They demonstrate that taurocholate synthesis is increasing rapidly during the final stages of gestation and show that cortisol augments taurocholate synthesis in a dose-response pattern.

Furan Induced Characteristic Glutathione S-Transferase Placental Form-Positive Foci in Terms of Cell Kinetics and Gene Expression

2020 ◽  
Vol 48 (6) ◽  
pp. 756-765
Author(s):  
Shinji Takasu ◽  
Yuji Ishii ◽  
Aki Kijima ◽  
Kumiko Ogawa ◽  
Sae Nakane ◽  
...  
Keyword(s):  
Gene Expression ◽  
Reporter Gene ◽  
Cell Kinetics ◽  
Hierarchical Cluster ◽  
Short Exposure ◽  
Distribution Analysis ◽  
Glutathione S Transferase ◽  
Preneoplastic Lesions ◽  
Kinetics Of ◽  
Cessation Of Treatment

Glutathione S-transferase placental form-positive (GST-P+) foci are markers of preneoplastic lesions in rat hepatocarcinogenesis. Our previous studies using reporter gene transgenic rats showed that furan, a hepatocarcinogen in rodents, rapidly induces the formation of GST-P+ foci after short exposure without reporter gene mutation. We hypothesized that GST-P+ foci induced by furan may have biological characteristics different from those induced by diethylnitrosamine (DEN), a genotoxic hepatocarcinogen. Accordingly, we compared the cell kinetics of GST-P+ foci after cessation of DEN treatment and performed comprehensive gene expression in DEN- or furan-induced GST-P+ foci. The number and area of DEN-induced GST-P+ foci were increased after cessation of treatment, whereas furan decreased these parameters. Size distribution analysis showed that large furan-induced GST-P+ foci disappeared after cessation of treatment. Hierarchical cluster analysis showed that all samples from GST-P+ foci induced by furan were separated from those induced by DEN. SOX9 expression was upregulated in furan-induced GST-P+ foci and was detected by immunohistochemistry in large furan-induced GST-P+ foci. Our results indicated that large furan-induced GST-P+ foci were quite different from DEN-induced GST-P+ foci at the molecular and cellular levels. And one of the properties of disappearing large GST-P+ foci were characterized by inclusion of hepatocytes expressing SOX9.

scholarly journals Use of Root Organ Cultures To Investigate the Interaction between Glomus intraradices and Pratylenchus coffeae

2003 ◽  
Vol 69 (7) ◽  
pp. 4308-4311 ◽  
Author(s):  
Annemie Elsen ◽  
Stephane Declerck ◽  
Dirk De Waele
Keyword(s):  
Organ Culture ◽  
Glomus Intraradices ◽  
Organ Cultures ◽  
Nematode Reproduction ◽  
Pratylenchus Coffeae ◽  
Root Organ Culture ◽  
Mycorrhizal Development ◽  
Transformed Carrot Roots

ABSTRACT The interaction between Glomus intraradices and Pratylenchus coffeae on transformed carrot roots was studied in root organ culture. G. intraradices provided the roots with increased protection against P. coffeae by suppressing nematode reproduction in the roots. The internal and external mycorrhizal development was not influenced by the presence of the nematodes.

CORRELATION BETWEEN THE EFFECTS OF HORMONES ON THE SYNTHESIS OF DNA IN EXPLANTS FROM INDUCED RAT MAMMARY TUMOURS AND THE GROWTH OF THE TUMOURS

1974 ◽  
Vol 62 (2) ◽  
pp. 225-240 ◽  
Author(s):  
D. LEWIS ◽  
R. C. HALLOWES
Keyword(s):  
Organ Culture ◽  
Dna Synthesis ◽  
Culture Medium ◽  
Mammary Glands ◽  
Sprague Dawley ◽  
Culture Techniques ◽  
Mammary Tumours ◽  
Sprague Dawley Rats

SUMMARY Explants from 32 mammary tumours induced in Sprague—Dawley rats by 9,10-dimethyl-1,2-benzanthracene (DMBA) were maintained in organ culture for up to 48 h. Insulin, corticosterone, prolactin, growth hormone and oestradiol were added to the culture medium in various combinations and their effects on the DNA synthesis of the explants was studied. DNA synthesis was stimulated by insulin in explants from 30 out of the 32 tumours examined and this group of 30 responsive tumours could be further subdivided. Explants from 16 tumours showed a greater rate of DNA synthesis in medium containing insulin plus corticosterone plus prolactin than in medium containing insulin alone and this higher rate was decreased by oestradiol; this group is referred to as 'prolactin-responsive'. Explants from the remaining 14 tumours did not show a greater rate of DNA synthesis in medium that contained insulin plus corticosterone plus prolactin than in medium containing insulin alone and neither rate was decreased by oestradiol; this group is referred to as 'insulin-responsive'. Explants from two tumours were not stimulated by insulin and these tumours are referred to as 'non-responsive'. After oophorectomy or administration of ergocryptine to tumour-bearing rats, the prolactin-responsive tumours regressed whereas the non-responsive tumours continued to grow. Explants taken from prolactin-responsive tumours 2 weeks after either oophorectomy or administration of ergocryptine were still prolactin-responsive but those taken from insulin-responsive tumours 2 weeks after the same treatment were now also prolactin-responsive. The non-responsive tumours remained non-responsive. The effects of hormones on the DNA synthesis in vitro of explants from growing DMBA-induced tumours were thus different from those on explants of mammary glands from virgin or pregnant Sprague—Dawley rats. It was concluded that it was possible to predict by organ culture techniques the response in vivo of growing mammary tumours to oophorectomy and ergocryptine administration.

Estrogen Affects Development of Alveolar Structures in Whole-Organ Culture of Mouse Mammary Glands

1997 ◽  
Vol 232 (2) ◽  
pp. 340-344 ◽  
Author(s):  
John Barlow ◽  
Theresa Casey ◽  
Jen-Fu Chiu ◽  
Karen Plaut
Keyword(s):  
Organ Culture ◽  
Mammary Glands
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