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1.
BMC Physiol ; 17(1): 7, 2017 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-28806941

RESUMO

BACKGROUND: Previous studies show that androgens are involved in hypertrophy and excitability of cardiomyocytes and that their effects are mediated through their receptor. The aim of this study was to evaluate the presence of androgen receptor (AR) in mouse heart during prenatal and early postnatal stages. RESULTS: The expression of AR and related genes, alpha myosin heavy chain -Myh6-, beta myosin heavy chain -Myh7- and atrial natriuretic factor -Nppa- was simultaneously evaluated by semiquantitative RT-PCR. AR was also detected by immunohistochemistry. Androgen receptor mRNA was detected in hearts from 10.5 days post coitum to 16 postnatal days. A higher expression of AR mRNA in atria compared to ventricles was observed in neonatal mouse. A positive correlation between mRNA levels of AR and Nppa was observed in mouse heart at early postnatal development. Androgen receptor expression is similar in males and females during cardiac development. Finally, androgen receptor protein was observed by immunohistochemistry in myocardial cells of atria and ventricles from 12.5 days onwards and restricted after 16.5 days post-coitum to nuclei of cardiomyocytes. CONCLUSION: Present results provide evidence that androgen receptor is expressed from prenatal stages in mouse heart, supporting the proposition that androgens could be involved in mammalian heart development.


Assuntos
Coração/embriologia , Miócitos Cardíacos/metabolismo , Receptores Androgênicos/metabolismo , Animais , Fator Natriurético Atrial , Feminino , Camundongos , Cadeias Pesadas de Miosina/metabolismo , Peptídeo Natriurético Tipo C/metabolismo , Precursores de Proteínas/metabolismo , RNA Mensageiro/metabolismo
2.
Endocr Connect ; 12(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37924640

RESUMO

The incidence of ovarian cancer has been epidemiologically related to female reproductive events and hormone replacement therapy after menopause. This highlights the importance of evaluating the role of sexual steroid hormones in ovarian cancer by the expression of enzymes related to steroid hormone biosynthesis in the tumor cells. This study was aimed to evaluate the presence of 17ß-hydroxysteroid dehydrogenase type 1 (17ß-HSD1), aromatase and estrogen receptor alpha (ERα) in the tumor cells and their association with the overall survival in 111 patients diagnosed with primary ovarian tumors. Positive immunoreactivity for 17ß-HSD1 was observed in 74% of the tumors. In the same samples, aromatase and ERα revealed 66% and 47% positivity, respectively. No association was observed of 17ß-HSD1 expression with the histological subtypes and clinical stages of the tumor. The overall survival of patients was improved in 17ß-HSD1-positive group in Kaplan-Meier analysis (P = 0.028), and 17ß-HSD1 expression had a protective effect from multivariate proportional regression evaluation (HR = 0.44; 95% CI 0.24-0.9; P = 0.040). The improved survival was observed in serous epithelial tumors but not in nonserous ovarian tumors. The expression of 17ß-HSD1 in the cells of the serous epithelial ovarian tumors was associated with an improved overall survival, whereas aromatase and ERα were not related to a better survival. The evaluation of hazard risk factors demonstrated that age and clinical stage showed worse prognosis, and 17ß-HSD1 expression displayed a protective effect with a better survival outcome in patients of epithelial ovarian tumors.

3.
Growth Factors ; 30(5): 297-303, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22765221

RESUMO

The expression pattern of transforming growth factor beta (TGFß) isoforms in chicken embryo gonads was studied at 6-10 days of incubation. TGFß2 mRNA was expressed predominantly in the cortex of the left ovary from day 8 of incubation onwards. TGFß3 mRNA was not detected at any of the stages studied. Similarly, immunofluorescence for the TGFß protein revealed that at day 9 it was located throughout the cortex of the left ovary and in the medulla of both the left and right ovaries. The presence of phosphorylated Smad2 in the nuclei of these regions suggests that TGFß signaling is most likely active at this developmental stage. Culturing the left ovary in a TGFß1-supplemented medium induced a shift of cortical structures toward the medulla, suggesting a role for TGFß in the morphogenesis of the female gonad in chickens.


Assuntos
Ovário/embriologia , Ovário/metabolismo , RNA Mensageiro/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Animais , Núcleo Celular/metabolismo , Embrião de Galinha , Feminino , Imunofluorescência , Morfogênese , Técnicas de Cultura de Órgãos , Fosforilação , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , RNA Mensageiro/genética , Transdução de Sinais , Proteína Smad2/metabolismo
4.
Gen Comp Endocrinol ; 175(2): 297-310, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22142535

RESUMO

Preovulatory follicular development (PFD) is mainly regulated by gonadotropins (FSH, LH) and steroids, although other intraovarian factors are also involved. We analyzed the local expression of growth hormone (GH) in the hen ovary and the role that this hormone may play on the regulation of steroidogenesis in granulosa cells (GCs). Ovarian follicles from sexually mature hens were studied at different developmental stages. Both GH mRNA (by in situ hybridization) and protein (by immunohistochemistry) were expressed mainly in the GCs, and to a lesser extent in the theca cells of the follicular wall. Sequence of a GH cDNA 690-bp fragment obtained from the follicular wall was identical to that obtained from the pituitary. The growth hormone receptor (GHR) mRNA was also expressed in the follicles. Nine GH variants were observed by SDS-PAGE and Western blotting, but the main isoform showed a MW of 17 kDa, at all developmental stages. Addition of GH (0.1, 1, 10 nM) stimulated the synthesis of progesterone (P4) in primary GCs cultures in a dose-dependent manner (1.5, 2.9, 5.4 times, respectively). GH also stimulated the expression of cholesterol side-chain cleavage enzyme (cytochrome P450scc) mRNA, a rate-limiting enzyme during P4 synthesis (2.9, 4.6, 4.9 times, respectively), whereas the synthesis of 3ß-hydroxysteroid dehydrogenase (3ß-HSD) mRNA (a constitutive enzyme) was not changed. Both GH and GHR were co-expressed in GCs cultures. The locally expressed GH present in concentrated (4×, 6×, 8×) conditioned media obtained from ovarian GC cultures stimulated P4 production (1.2, 2.2, 4.4 times, respectively) in additional fresh cultured GCs, and this effect disappeared when the conditioned media were treated with antiserum against GH. These data suggest that locally produced GH may modulate follicular development through autocrine/paracrine effects in the chicken ovary.


Assuntos
Galinhas/metabolismo , Células da Granulosa/metabolismo , Hormônio do Crescimento/metabolismo , Ovário/metabolismo , Progesterona/biossíntese , Receptores da Somatotropina/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Células Cultivadas , Galinhas/crescimento & desenvolvimento , Eletroforese em Gel de Poliacrilamida , Feminino , Hormônio do Crescimento/química , Dados de Sequência Molecular , RNA Mensageiro/metabolismo
5.
Gen Comp Endocrinol ; 174(3): 344-7, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22019531

RESUMO

Cadherins are adhesion molecules that play a crucial role in tissue morphogenesis. Studies on N-cadherin and E-cadherin in the ovary of fetal hamster suggest that these adhesion molecules are involved in primordial follicle formation. In chicken embryo, present results demonstrate that N-cadherin is located on the surface epithelium and in the cortical cords of the ovary. Moreover, N-cadherin is identified in germ cells on day 14 of chicken embryo development. Quantification of mRNA of N-cadherin and E-cadherin demonstrates that treatments with follicle-stimulating hormone (FSH) or human chorionic gonadotropin (hCG), increase N-cadherin expression. Whereas, E-cadherin expression is decreased by gonadotropin treatments. The negative correlation between both cadherins expression is demonstrated after 18 h of hormonal treatment. Regulation of cadherin expression by gonadotropins and the presence of N-cadherin in the ovarian cortex suggest that these adhesion molecules are involved in ovarian morphogenesis in the chicken embryo.


Assuntos
Caderinas/genética , Embrião de Galinha/metabolismo , Gonadotropinas/fisiologia , Ovário/metabolismo , Animais , Caderinas/metabolismo , Células Cultivadas , Gonadotropina Coriônica/farmacologia , Feminino , Imunofluorescência , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Gonadotropinas/farmacologia , Humanos , Morfogênese/efeitos dos fármacos , Morfogênese/genética , Morfogênese/fisiologia , Ovário/citologia , Ovário/efeitos dos fármacos , Ovário/embriologia , Cultura Primária de Células , Reação em Cadeia da Polimerase Via Transcriptase Reversa
6.
J Ovarian Res ; 14(1): 98, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34321053

RESUMO

BACKGROUND: Ovarian cancer is usually diagnosed at an advanced stage due to its early asymptomatic course and late-stage non-specific symptoms. This highlights the importance of researching the molecular mechanisms involved in ovarian carcinogenesis as well as the discovery of novel prognostic markers that could help improve the survival outcome of patients. The aim of this study was to evaluate the expression of the steroid sulfatase (STS) in 154 samples of primary ovarian tumors. This protein is crucial in the intracellular conversion of sulfated steroid hormones to active steroid hormones. The presence of STS, 3ß-HSD, and 17ß-HSD1 result in the production of testosterone which act through the androgen receptor (AR) in the tumor cell. The presence of STS and AR in epithelial ovarian tumors and their association to the overall survival of patients was evaluated using Kaplan-Meier and Cox regression analyses. RESULTS: Immunoreactivity for STS was detected in 65% of the tumors and no association was observed with histological subtypes and clinical stages of the tumor. The STS expression in the tumors exhibiting immunoreactive AR resulted in a reduced survival (log-rank test, p = 0.032) and a risk factor in univariate and multivariate analysis, HR = 3.46, CI95% 1.00-11.92, p = 0.049 and HR = 5.92, CI95% 1.34-26.09, p = 0.019, respectively. CONCLUSIONS: These findings suggest that the intracellular synthesis of testosterone acting through its receptor can promote tumor growth and progression. Moreover, the simultaneous expression of STS and AR constitutes an independent predictor of poor prognosis in epithelial ovarian tumors.


Assuntos
Carcinoma Epitelial do Ovário/genética , Receptores Androgênicos/metabolismo , Esteril-Sulfatase/metabolismo , Adulto , Carcinoma Epitelial do Ovário/mortalidade , Feminino , Humanos , Pessoa de Meia-Idade , Análise de Sobrevida
7.
J Ovarian Res ; 13(1): 86, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32718331

RESUMO

BACKGROUND: The current study evaluated the metalloproteinases MMP-2 and MMP-9 expression in epithelial cells and the surrounding stroma in ovarian tumors and the association of MMPs with the histological subtypes, the clinical stage and the presence of steroid hormone receptors. Tumor samples were obtained from 88 patients undergoing surgical cytoreduction of primary ovarian tumors in Instituto Nacional de Cancerología, from México City. The formalin fixed and paraffin embedded samples were processed in order to demonstrate the presence of androgen receptor,estrogen receptor alpha, progesterone receptor, MMP-2,MMP-9 and collagen IV by immunohistochemistry and/or immunofluorescence. RESULTS: MMP-2 and MMP-9 were differentially expressed in the epithelium and the stroma of ovarian tumors associated to histological subtype, clinical stage and sexual steroid hormone receptor expression. Based on Cox proportional hazard regression model we demonstrated that MMP-2 located in the epithelium and the stroma are independent prognostic biomarkers for overall survival in epithelial ovarian tumors. Kaplan Meir analysis of the combination of AR (+) with MMP-2 (+) in epithelium and AR (+) with MMP-2 (-) in stroma displayed a significant reduction of survival. CONCLUSIONS: The presence of MMP-2 in the stroma of the tumor was a protective factor while the presence of MMP-2 in the epithelium indicated an adverse prognosis. The presence of AR associated with MMP-2 in the tumor cells was a risk factor for overall survival in epithelial ovarian cancer.


Assuntos
Carcinoma Epitelial do Ovário/patologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Neoplasias Ovarianas/patologia , Receptores Androgênicos/metabolismo , Adulto , Carcinoma Epitelial do Ovário/metabolismo , Epitélio/metabolismo , Epitélio/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/metabolismo , Prognóstico , Estudos Retrospectivos , Células Estromais/metabolismo , Células Estromais/patologia , Análise de Sobrevida
8.
J Ovarian Res ; 12(1): 15, 2019 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-30736825

RESUMO

BACKGROUND: Ovarian cancer is the most lethal of all gynecologic malignancies. The relationship between sexual steroids receptors and ovarian cancer progression has been largely evaluated. The presence of progesterone receptors has been associated with an increase of a disease-free period and overall survival in patients with ovarian carcinoma. In the present study, primary cultures of ovarian carcinoma obtained from 35 patients diagnosed with epithelial ovarian cancer were evaluated for cell survival after treatment with 10- 8 M of 17ß-estradiol, progesterone, testosterone and dihydrotestosterone. RESULTS: The results were analyzed considering histological subtypes: low grade serous, high grade serous, endometrioid and mucinous carcinoma; clear cell carcinoma was not included due to failure in obtaining successful cultures of this subtype. A significant reduction of cell survival was observed after progesterone treatment in endometrioid ovarian carcinoma. Changes were not observed in low grade serous, high grade serous and mucinous carcinoma. The effect of progesterone was related to the presence of progesterone receptor (PR), a 43% reduction in the cell number was observed in PR (+) endometrioid ovarian carcinoma. CONCLUSIONS: This study supports the importance of progesterone and the presence of progesterone receptor in the reduction of ovarian cancer progression in the endometrioid ovarian carcinoma.


Assuntos
Antineoplásicos Hormonais/farmacologia , Carcinoma Endometrioide/patologia , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Ovarianas/patologia , Progesterona/farmacologia , Adulto , Carcinoma Endometrioide/metabolismo , Carcinoma Epitelial do Ovário/metabolismo , Carcinoma Epitelial do Ovário/patologia , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/metabolismo , Estudos Prospectivos , Receptores de Progesterona/metabolismo , Receptores de Esteroides/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos
9.
Endocr Connect ; 7(9): 1006-1012, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30012649

RESUMO

The significance of the presence of androgen receptor (AR), estrogen receptor alpha (ER) and progesterone receptor (PR) in ovarian cancer patient survival has been a matter of numerous studies. This study was aimed to describe the expression profile of the three sexual steroid receptors in high-grade serous, endometrioid, mucinous and low-grade serous ovarian carcinoma and its association to the proliferation index in patients with primary ovarian carcinoma diagnosis, before any treatment. Eighty-one samples were obtained from the National Institute of Cancerology in Mexico City and were evaluated for the presence of AR, ER, PR and Ki67 by immunohistochemistry. The four subtypes of ovarian carcinoma displays a specific profile of the eight possible combinations of the steroid receptors with significant differences within the profile and the histological subtypes. High-grade serous carcinoma was characterized by a high frequency of both, triple-negative and AR+ ER- PR+ profiles. Endometrioid carcinoma presented a higher frequency of triple-positive profile. The presence of only AR+ profile was not observed in the endometrioid tumors. The relationship of the receptor profile with the proliferation index in the tumor epithelium shows that the expression of only ER is associated to a reduced proliferation index in endometrioid carcinoma. Steroid hormone receptor expression and co-expression could help characterize ovarian carcinoma.

10.
J Ovarian Res ; 9(1): 41, 2016 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-27388275

RESUMO

BACKGROUND: Serum levels of CA125 measured before any treatment have been evaluated in epithelial ovarian cancer (EOC) as a predictor of patient survival; however, results in survival index are controversial, as CA125 levels are influenced by several variables. Taking this into consideration, the present study evaluated the association of pretreatment levels of CA125 serum with the clinical stage, histology and differentiation grade of the tumor and the survival rate in a group of patients from an oncology referral center in Mexico, all of them diagnosed with ovarian carcinoma. This retrospective study consisted of 1009 patients with EOC, diagnosed between 2006 and 2013 at the National Cancerology Institute (Instituto Nacional de Cancerología-INCan), considering only those with CA125 measurements before any chemotherapy or surgical cytoreduction. Patients with three years of medical follow-up having pretreatment CA125 value and simultaneous diagnoses of histological subtype, clinical stage and differentiation grade of the tumor (n = 656) were studied in order to determine their survival rate. RESULTS: The abnormal level (>35 U/mL) of CA125 was observed in 99 % of serous carcinoma cases rated I to IV in the FIGO stages. Abnormal CA125 proportions were 89 % in endometrioid subtype and 69 % in mucinous tumors, with the highest absolute value of CA125 observed in serous carcinoma surpassing any other histological subtype. Clinical stages III and IV displayed increased CA125 values compared to stages I and II. Undifferentiated carcinomas show the highest level of this indicator compared with those of low and moderate differentiated grade. Survival evaluation by Kaplan-Meier analysis including only high grade serous carcinoma at FIGO stage III (n = 57) demonstrated 57.1 % chances of survival in patients with CA125 pretreatment levels higher than 500 U/mL. Survival was 26.7 % in patients with CA125 lower than 500 U/mL and the hazard ratio for CA125 ≤ 500 U/mL was 2.28, 95 % CI 1.08-4.84, P = 0.032. CONCLUSIONS: Clinical stage associated with pretreatment absolute values of CA125 should be considered as prognostic factor in EOC patients. Values of CA125 higher than 500 U/mL in high grade serous carcinoma with FIGO stage III resulted in an enhanced survival rate of the patients.


Assuntos
Biomarcadores Tumorais , Antígeno Ca-125/sangue , Cistadenocarcinoma Seroso/sangue , Cistadenocarcinoma Seroso/mortalidade , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cistadenocarcinoma Seroso/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias Ovarianas/patologia , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Adulto Jovem
11.
J Ovarian Res ; 6(1): 85, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24279585

RESUMO

BACKGROUND: The importance of surface epithelium and epithelial inclusion cysts in the ovary arises from studies demonstrating that these structures are susceptible to epithelial ovarian cancer development. The expression of estrogen receptor alpha (ER alpha), androgen receptor (AR), in epithelial cells of the ovary from premenopausal and postmenopausal women is interesting because sexual steroid hormones are involved in cell growth and differentiation. METHODS: The presence of ER alpha, AR, and the orphan G protein-coupled receptor 30 (GPR30) was demonstrated by immunofluorescence in ovaries obtained from 79 pre and postmenopausal patients, undergoing histero-salpingo-oophorectomy for proliferative gynecological diseases. The proportion of patients that displayed positive reaction for estrogen and androgen receptors in epithelial cells of the ovary was evaluated according to menopausal status and associated pathology. RESULTS: The proportion of patients that displayed a positive receptor expression in the epithelial cells of the ovarian surface and cortical inclusion cysts shows that ER alpha is present in 20 of 79 patients (0.25), AR in 33 of 79 (0.42) and GPR30 in 38 of 55 (0.69). There are no differences in ER alpha, AR, and GPR30 expression between pre and postmenopausal patients and considering the associated pathology, proportions for ER alpha and GPR30 are similar. The patients with cervical cancer show a higher proportion of AR expression in epithelial cells of the ovary, which is statistically significant (P < 0.01) compared with patients with other proliferative diseases. CONCLUSIONS: The presence of ER alpha, AR, and GPR30 in the surface epithelial ovarian cells and its derivatives are observed with a proportion that is specific for each receptor. The proportion of expression for these receptors in the epithelial cells of the ovary does not change after menopause. The proportion of ovaries with AR positive epithelial cells in patients with cervical squamous carcinoma is higher compared with other gynecological pathologies.

12.
Neuroreport ; 20(5): 513-6, 2009 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-19262415

RESUMO

Androgen effects, mediated by the androgen receptor, regulate important cellular processes such as growth, proliferation, and differentiation. The presence of androgen receptor has been described in structures of the central nervous system, mainly in advanced fetuses, newborns, and adult animals. This study describes the presence and location of androgen receptor in early developmental stages of the nervous system. The androgen receptor mRNA was evidenced through reverse transcriptase-PCR and the androgen receptor protein by immunohistochemistry and western blot techniques in the cerebral vesicles of 9.5-day mouse embryos and chicken embryos at stages 8-17 of Hamburger and Hamilton. The androgen receptor protein was located in the nucleus of neuroepithelial cells throughout the neural tube.


Assuntos
Sistema Nervoso Central/embriologia , Sistema Nervoso Central/metabolismo , Tubo Neural/metabolismo , Receptores Androgênicos/metabolismo , Animais , Western Blotting , Embrião de Galinha , Imuno-Histoquímica , Camundongos , Células Neuroepiteliais/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Cell Tissue Res ; 325(1): 143-9, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16525833

RESUMO

The gonadal development of chicken embryo is regulated by hormones and growth factors. Transforming growth factor beta (TGF-beta) isoforms may play a critical role in the regulation of growth in chicken gonads. We have investigated the effect of the TGF-beta isoforms on the number of germ and somatic cells in the ovary of the chicken embryo. Ovaries were obtained from chicken embryos at 9 days of incubation. They were organ-cultured for 72 h in groups treated with TGF-beta1, TGF-beta2, soluble betaglycan, TGF-beta1 plus soluble betaglycan, or TGF-beta2 plus soluble betaglycan, and untreated (control). TGF-beta1 and TGF-beta2 diminished the somatic cell number in the ovary of the chicken embryo at this age by inhibiting the proliferation of the somatic cells without increasing apoptosis. On the other hand, TGF-beta1 and TGF-beta2 did not affect the number of germ cells in the cultured ovary. The capacity of TGF-beta1 and TGF-beta2 to diminish the number of somatic cells in the ovary was blocked with soluble betaglycan, a natural TGF-beta antagonist. However, changes in the location of germ cells within the ovary suggested that TGF-beta promoted the migration of the germ cells from the ovarian cortex to the medulla. Thus, TGF-beta affects germ and somatic cells in the ovary of the 9-day-old chicken embryo and inhibits the proliferation of somatic cells.


Assuntos
Embrião de Galinha/embriologia , Ovário/embriologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Contagem de Células , Divisão Celular , Embrião de Galinha/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Técnicas de Cultura de Órgãos , Ovário/citologia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteoglicanas/metabolismo , Proteoglicanas/fisiologia , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/fisiologia , Proteínas Recombinantes/metabolismo , Fator de Crescimento Transformador beta/genética
14.
J Exp Zool A Comp Exp Biol ; 303(3): 179-85, 2005 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15726631

RESUMO

The aim of the present study was to evaluate the effect of hypophysectomy on cell proliferation in the left ovary and the left testis of 8- to 14-day-old chick embryos. Hypophysectomy was performed by the partial decapitation technique. At 44-46 h of incubation, chick embryo heads were sectioned at the mesencephalic level and the prosencephalic region removed. Embryos were further incubated until 8-14 days of development. Cell division was evaluated by bromodeoxyuridine (BrdU) incorporation and by counting the total number of somatic and germ cells in the gonads. The ovary displayed an exponential increase in the number of somatic and germ cells and a higher rate of BrdU incorporation compared to the testis. BrdU incorporation was reduced in the ovary of hypophysectomized embryos at 9-14 days of incubation, while in the testis, the reduction was significant at 14 days of development. Changes in the total number of somatic and germ cells further suggest that the absence of hypophysis affects the growth of the ovary earlier than the growth of the testis. Reduction in the number of somatic and germ cells after hypophysectomy in the ovary was reversed by a hypophyseal graft on the chorioallantoic membrane. The adenohypophysis regulates, probably through gonadotropic hormones, proliferation of somatic and germ cells in the gonads during chick embryo development.


Assuntos
Proliferação de Células , Ovário/embriologia , Adeno-Hipófise/fisiologia , Testículo/embriologia , Animais , Embrião de Galinha/crescimento & desenvolvimento , Feminino , Masculino
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