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BACKGROUND: The male and female prostates are controlled by steroid hormones, suffering important morphological and physiological changes after castration. Prolactin is involved in the regulation of the male prostate, having already been identified in the tissue, acting through its receptor PRLR. In the Mongolian gerbil, in addition to the male prostate, the female prostate is also well developed and active in its secretion processes. The aim of the present study was to evaluate the effects of exposure to exogenous prolactin in the prostate of both intact and castrated male and female gerbils in order to establish if prolactin administration can sustain prostate cell activity in conditions of sexual hormone deprivation. METHODS: The morphological analyses were performed by biometric analysis, lesion histological analysis and morphometric-stereological aspects. In addition, immune-cytochemical tests were performed for prolactin and its receptor, as well as for the receptors of androgen and oestrogen and serum prolactin dosage. All data were submitted to ANOVA or Kruskal-Wallis tests for comparison between groups. P < 0.05 was considered to be statistically significant. RESULTS: The results showed a strong influence of prolactin on the morphology of the prostate, with the development of important epithelial alterations, after only 3 days of administration, and an expressive epithelial cell discard process after 30 days of administration. Prolactin acts in synergy with testosterone in males and mainly with oestrogens in females, establishing different steroid hormonal receptor immunoreactivity according to sex. It was also demonstrated that prolactin can assist in the recovery from some atrophic effects caused in the gland after castration, without causing additional tissue damage. CONCLUSIONS: The prolactin and its receptor are involved in the maintenance of the homeostasis of male and female gerbils, and also cause distinct histological alterations after exogenous exposure for 3 and 30 days. The effects of prolactin are related to its joint action on androgens and oestrogens and it can also assist in the recovery from the atrophic effects of castration.

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During puberty, sexual hormones induce crucial changes in neural circuit organization, leading to significant sexual dimorphism in adult behaviours. The ventrolateral division of the ventromedial nucleus of the hypothalamus (VMHvl) is the major neural site controlling the receptive component of female sexual behaviour, which is dependent on ovarian hormones. The inputs to the VMHvl, originating from the medial nucleus of the amygdala (MeA), transmit essential information to trigger such behaviour. In this study, we investigated the projection pattern of the MeA to the VMHvl in ovariectomized rats at early puberty. Six-week-old Sprague-Dawley rats were ovariectomized (OVX) and, upon reaching 90 days of age, were subjected to iontophoretic injections of the neuronal anterograde tracer Phaseolus vulgaris leucoagglutinin into the MeA. Projections from the MeA to the VMHvl and to other structures included in the neural circuit responsible for female sexual behaviour were analysed in the Control and OVX groups. The results of the semi-quantitative analysis showed that peripubertal ovariectomy reduced the density of intra-amygdalar fibres. The stereological estimates, however, failed to find changes in the organization of the terminal fields of nerve fibres from the MeA to the VMHvl in the adult. The present data show that ovariectomized rats during the peripubertal phase did not undergo significant changes in MeA fibres reaching the VMHvl; however, they suggest a possible effect of ovariectomy on MeA connectivity under amygdalar subnuclei.

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Sex differences in the immune response can also affect the febrile response, particularly the fever induced by lipopolysaccharide (LPS). However, other pathogen-associated molecular patterns, such as zymosan A (Zym) and polyinosinic-polycytidylic acid (Poly I:C), also induce fever in male rats with a different time course of cytokine release and different mediators such as endothelin-1 (ET-1). This study investigated whether female sex hormones affect Zym- and Poly I:C-induced fever and the involvement of ET-1 in this response. The fever that was induced by Zym and Poly I:C was higher in ovariectomized (OVX) female rats compared with sham-operated female rats. Estrogen replacement in OVX females reduced Zym- and Poly I:C-induced fever. The ETB receptor antagonist BQ788 reversed the LPS-induced fever in cycling females but not in OVX females. BQ788 did not alter the fever that was induced by Zym or Poly I:C in either cycling or OVX females. These findings suggest that the febrile response in cycling females is lower, independently of the stimulus that is inducing it and is probably controlled by estrogen. Also, ET-1 seems to participate in the febrile response that was induced by LPS in males and cycling females but not in the LPS-induced fever in OVX females. Additionally, ET-1 was not involved in the febrile response that was induced by Zym or Poly I:C in females.

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Astrocytes are dynamic glial cells that maintain brain homeostasis, particularly metabolic functions, inflammatory response, and antioxidant defense. Since menopause may be associated with brain dysfunction, in the present study, we evaluated anti- and proinflammatory cytokine release in cortical and hippocampal astrocyte cultures obtained from adult female Wistar rats subjected to ovariectomy, a known experimental model of menopause. We also tested some parameters of metabolic functionality (Na+, K+-ATPase activity) and cellular redox status, such as antioxidant enzyme defenses (superoxide dismutase and catalase) and the intracellular production of reactive oxygen species in this experimental model. Female adult Wistar rats (180 days-age) were assigned to one of the following groups: sham (submitted to surgery without removal of the ovaries) and ovariectomy (submitted to surgery to removal of the ovaries). Thirty days after ovariectomy or sham surgery, we prepared astrocyte cultures from control and ovariectomy surgery animals. Ovariectomized rats presented an increase in pro-inflammatory cytokines (tumor necrosis factor α, interleukins 1ß, 6, and 18) and a decrease in interleukin 10 release, an anti-inflammatory cytokine, in cortical and hippocampal astrocytes, when compared to those obtained from sham group (control). In addition, Na+,K+-ATPase activity decreased in hippocampal astrocytes, but not in cortical astrocyte cultures. In contrast, antioxidant enzymes did not alter in cortical astrocyte cultures, but increased in hippocampal astrocytes. In summary, our findings suggest that ovariectomy is able to induce an inflammatory response in vivo, which could be detected in in vitro astrocytes after approximately 4 weeks.

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O objetivo deste trabalho foi avaliar os efeitos cardiorrespiratórios de duas doses de fentanil associadas à lidocaína e cetamina em fêmeas caninas anestesiadas com sevoflurano e submetidas à ovariohisterectomia eletiva. Foram utilizados 18 animais distribuídos aleatoriamente em dois grupos. Os animais do grupo A (GA) receberam pela via intravenosa um bolus de fentanil de 0,0018 mg/kg e os do grupo B (GB) 0,0036 mg/kg, ambos associados a lidocaína 3 mg/kg e cetamina 0,6 mg/kg. Imediatamente após o bolus realizou-se a indução com propofol seguido do início da infusão contínua (IC) de fentanil na dose de 0,0018 mg/kg/h para o GA e 0,0036 mg/kg/h para GB, ambos associados a 3 e 0,6 mg/kg/h de lidocaína e cetamina. A anestesia foi mantida com sevoflurano diluído em oxigênio 100% a 1,5V% por meio de vaporizador calibrado que foi ajustado para a manutenção do plano anestésico cirúrgico. Os animais foram posicionados em decúbito dorsal e permaneceram sob ventilação espontânea. Foram avaliados os valores basais (T0), após indução (T1) e 5 (T5), 20 (T20) e 35 (T35) minutos de IC dos seguintes parâmetros: frequência cardíaca (FC), frequência respiratória (f), pressão arterial sistólica (PAS), diastólica (PAD) e média (PAM), saturação de oxigênio na hemoglobina (SatO2), pressão parcial de dióxido de carbono (EtCO2) e o sevoflurano expirado (EtSevo). A análise estatística foi realizada através da análise de variância seguida do teste de Scott-knott. As diferenças foram consideradas significativas quando P< 0,05. A FC reduziu após 20 minutos de IC e a f, PAS, PAD e PAM diminuíram após indução anestésica. Tais diferenças não foram relevantes clinicamente e os valores se mantiveram dentro do limite fisiológico. Pode-se concluir que as duas doses de infusão contínua de fentanil produziram estabilidade cardiovascular e respiratória, além de permitirem a diminuição do requerimento de sevoflurano para a realização da ovariohisterectomia eletiva.(AU)

The aim of this study was to evaluate the cardiorespiratory effects of two doses of fentanyl associated with lidocaine and ketamine in canine females anesthetized with sevoflurane and submitted to elective ovariohysterectomy. 18 animals were randomly assigned to two groups. Group A (GA) animals received a loading dose intravenously of fentanyl 0.0018 mg/kg and those of group B (GB) 0.0036 mg/kg, both associated with lidocaine 3 mg/kg and ketamine 0, 6 mg/kg. Immediately after the loading dose, induction with propofol was realized followed by continuous infusion (CI) of fentanyl at the dose of 0.0018 mg/kg/h for GA and 0.0036 mg/kg/h for GB, both associated to 3 and 0.6 mg/kg/h of lidocaine and ketamine. The anesthesia was maintained with sevoflurane diluted in 100% oxygen at 1.5% by a calibrated vaporizer that was adjusted for the maintenance of the surgical anesthetic plane. The animals were placed in dorsal decubitus position and remained under spontaneous ventilation. Was evaluated the baseline values (T0), after induction (T1) and 5 (T5), 20 (T20) and 35 (T35) minutes of following parameters: heart rate (HR), respiratory rate (f), systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean blood pressure (MAP), oxygen saturation in hemoglobin (SatO2), partial carbon dioxide (EtCO2) pressure and expired sevoflurane (EtSevo). Statistical analysis was performed through analysis of variance followed by the Scott-knott test. Differences were considered significant when P< 0.05. HR decreased after 20 minutes of CI and f, SBP, DBP and MAP decreased after anesthetic induction. These differences were not clinically relevant and the values remained within the physiological limit. It can be concluded that the two doses of continuous infusion of fentanyl produced cardiovascular and respiratory stability, besides allowing the reduction of the sevoflurane requirement for elective ovariohysterectomy.(AU)

El objetivo de este trabajo fue evaluar los efectos cardiorrespiratorios de dos dosis de fentanil asociadas a la lidocaína y cetamina en perras anestesiadas con sevoflurane y sometidas a la ovariohisterectomía electiva. Se utilizaron 18 animales distribuidos aleatoriamente en dos grupos. Los animales del grupo A (GA) recibieron por vía intravenosa un bolus de fentanil de 0,0018 mg/kg y los del grupo B (GB) 0,0036 mg/kg, ambos asociados a lidocaína 3 mg/kg y cetamina 0,6 mg/kg. Inmediatamente después del bolus se realizó la inducción con propofol seguido del inicio de la infusión continua (IC) de fentanil a la dosis de 0,0018 mg/kg/h para el GA y 0,0036 mg/kg/h para GB, ambos asociados a 3 y 0,6 mg/kg/h de lidocaína y cetamina. La anestesia fue mantenida con sevoflurane diluido en oxígeno 100% a 1,5V% a través de vaporizador calibrado que fue ajustado para el mantenimiento del plano anestésico quirúrgico. Los animales fueron colocados en decúbito dorsal y permanecieron bajo ventilación espontánea. Se evaluaron los valores basales (T0), después de la inducción (T1) y 5 (T5), 20 (T20) y 35 (T35) minutos de IC de los siguientes parámetros: frecuencia cardíaca (FC), frecuencia respiratoria (f), presión arterial sistólica (PAS), presión arterial diastólica (PAD) y presión arterial media (PAM), saturación de oxígeno en la hemoglobina (SatO2), presión parcial de dióxido de carbón (EtCO2) y el sevoflurane expirado (EtSevo). El análisis estadístico fue realizado a través del análisis de varianza seguida de la prueba de Scott-knott. Las diferencias se consideraron significativas cuando P< 0,05. La FC redujo después de 20 minutos de IC y la f, PAS, PAD y PAM disminuyeron después de la inducción anestésica. Estas diferencias no fueron relevantes clínicamente y los valores se mantuvieron dentro del límite fisiológico. Se puede concluir que las dos dosis de infusión continua de fentanil produjeron estabilidad cardiovascular y respiratoria, además de permitir la disminución del requerimiento de sevoflurane para la realización de la ovariohisterectomía electiva.(AU)

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NEW FINDINGS: What is the central question of this study? Can Na+ depletion mobilize Na+ from the skin reservoir in ovariectomized rats? Does oestrogen replacement change the amount and the dynamics of skin Na+ storage? Is the reduced salt appetite after Na+ depletion in ovariectomized rats with oestrogen replacement related to changes in the skin Na+ ? What is the main finding and its importance? This work demonstrated that acute body Na+ depletion induced by frusemide mobilized the osmotically inactive skin Na+ reservoir to become osmotically active. Oestrogen treatment decreased the induced Na+ intake in ovariectomized rats but did not modulate the inactive Na+ reservoir in control conditions or its mobilization induced by Na+ depletion. ABSTRACT: Oestradiol, which is an important hormone for water and electrolyte balance, also has a role in the inhibition of induced Na+ appetite. Sodium can be stored in the skin in osmotically active or inactive forms, and this skin Na+ reservoir may be involved in the control of body Na+ levels during physiopathological challenges. In this study, we investigated whether the effect of sodium depletion by frusemide can mobilize Na+ from the skin reservoir and whether oestradiol replacement changes or mobilizes the Na+ reserves in the skin. Ovariectomized Wistar rats were treated with vehicle or oestradiol for 7 days to evaluate the effects of oestrogen on the hydroelectrolyte balance, intake responses and skin Na+ and water content in basal conditions. Furthermore, the effects of oestrogen were evaluated after 24 h frusemide-induced whole-body Na+ depletion. Oestradiol-replaced rats exhibited reduced water intake without any significant changes in salt intake, Na+ excretion or water and Na+ skin content in basal conditions. After sodium depletion, both vehicle- and oestradiol-treated rats exhibited an increase in the osmotically active skin Na+ , which was associated with a decrease of the inactive skin Na+ reservoir. Oestrogen decreased the hypertonic saline intake induced by Na+ depletion, but it was not associated with any significant changes in the skin Na+ reservoir. Thus, sodium depletion is able to change the inactive-active skin Na+ reservoir balance. However, the oestrogenic modulation of sodium appetite after Na+ depletion is probably not related to the action of this hormone in the skin Na+ reservoir balance.

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O objetivo deste trabalho foi avaliar os efeitos cardiorrespiratórios de duas doses de fentanil associadas à lidocaína e cetamina em fêmeas caninas anestesiadas com sevoflurano e submetidas à ovariohisterectomia eletiva. Foram utilizados 18 animais distribuídos aleatoriamente em dois grupos. Os animais do grupo A (GA) receberam pela via intravenosa um bolus de fentanil de 0,0018 mg/kg e os do grupo B (GB) 0,0036 mg/kg, ambos associados a lidocaína 3 mg/kg e cetamina 0,6 mg/kg. Imediatamente após o bolus realizou-se a indução com propofol seguido do início da infusão contínua (IC) de fentanil na dose de 0,0018 mg/kg/h para o GA e 0,0036 mg/kg/h para GB, ambos associados a 3 e 0,6 mg/kg/h de lidocaína e cetamina. A anestesia foi mantida com sevoflurano diluído em oxigênio 100% a 1,5V% por meio de vaporizador calibrado que foi ajustado para a manutenção do plano anestésico cirúrgico. Os animais foram posicionados em decúbito dorsal e permaneceram sob ventilação espontânea. Foram avaliados os valores basais (T0), após indução (T1) e 5 (T5), 20 (T20) e 35 (T35) minutos de IC dos seguintes parâmetros: frequência cardíaca (FC), frequência respiratória (f), pressão arterial sistólica (PAS), diastólica (PAD) e média (PAM), saturação de oxigênio na hemoglobina (SatO2), pressão parcial de dióxido de carbono (EtCO2) e o sevoflurano expirado (EtSevo). A análise estatística foi realizada através da análise de variância seguida do teste de Scott-knott. As diferenças foram consideradas significativas quando P< 0,05. A FC reduziu após 20 minutos de IC e a f, PAS, PAD e PAM diminuíram após indução anestésica. Tais diferenças não foram relevantes clinicamente e os valores se mantiveram dentro do limite fisiológico. Pode-se concluir que as duas doses de infusão contínua de fentanil produziram estabilidade cardiovascular e respiratória, além de permitirem a diminuição do requerimento de sevoflurano para a realização da ovariohisterectomia eletiva.

The aim of this study was to evaluate the cardiorespiratory effects of two doses of fentanyl associated with lidocaine and ketamine in canine females anesthetized with sevoflurane and submitted to elective ovariohysterectomy. 18 animals were randomly assigned to two groups. Group A (GA) animals received a loading dose intravenously of fentanyl 0.0018 mg/kg and those of group B (GB) 0.0036 mg/kg, both associated with lidocaine 3 mg/kg and ketamine 0, 6 mg/kg. Immediately after the loading dose, induction with propofol was realized followed by continuous infusion (CI) of fentanyl at the dose of 0.0018 mg/kg/h for GA and 0.0036 mg/kg/h for GB, both associated to 3 and 0.6 mg/kg/h of lidocaine and ketamine. The anesthesia was maintained with sevoflurane diluted in 100% oxygen at 1.5% by a calibrated vaporizer that was adjusted for the maintenance of the surgical anesthetic plane. The animals were placed in dorsal decubitus position and remained under spontaneous ventilation. Was evaluated the baseline values (T0), after induction (T1) and 5 (T5), 20 (T20) and 35 (T35) minutes of following parameters: heart rate (HR), respiratory rate (f), systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean blood pressure (MAP), oxygen saturation in hemoglobin (SatO2), partial carbon dioxide (EtCO2) pressure and expired sevoflurane (EtSevo). Statistical analysis was performed through analysis of variance followed by the Scott-knott test. Differences were considered significant when P< 0.05. HR decreased after 20 minutes of CI and f, SBP, DBP and MAP decreased after anesthetic induction. These differences were not clinically relevant and the values remained within the physiological limit. It can be concluded that the two doses of continuous infusion of fentanyl produced cardiovascular and respiratory stability, besides allowing the reduction of the sevoflurane requirement for elective ovariohysterectomy.

El objetivo de este trabajo fue evaluar los efectos cardiorrespiratorios de dos dosis de fentanil asociadas a la lidocaína y cetamina en perras anestesiadas con sevoflurane y sometidas a la ovariohisterectomía electiva. Se utilizaron 18 animales distribuidos aleatoriamente en dos grupos. Los animales del grupo A (GA) recibieron por vía intravenosa un bolus de fentanil de 0,0018 mg/kg y los del grupo B (GB) 0,0036 mg/kg, ambos asociados a lidocaína 3 mg/kg y cetamina 0,6 mg/kg. Inmediatamente después del bolus se realizó la inducción con propofol seguido del inicio de la infusión continua (IC) de fentanil a la dosis de 0,0018 mg/kg/h para el GA y 0,0036 mg/kg/h para GB, ambos asociados a 3 y 0,6 mg/kg/h de lidocaína y cetamina. La anestesia fue mantenida con sevoflurane diluido en oxígeno 100% a 1,5V% a través de vaporizador calibrado que fue ajustado para el mantenimiento del plano anestésico quirúrgico. Los animales fueron colocados en decúbito dorsal y permanecieron bajo ventilación espontánea. Se evaluaron los valores basales (T0), después de la inducción (T1) y 5 (T5), 20 (T20) y 35 (T35) minutos de IC de los siguientes parámetros: frecuencia cardíaca (FC), frecuencia respiratoria (f), presión arterial sistólica (PAS), presión arterial diastólica (PAD) y presión arterial media (PAM), saturación de oxígeno en la hemoglobina (SatO2), presión parcial de dióxido de carbón (EtCO2) y el sevoflurane expirado (EtSevo). El análisis estadístico fue realizado a través del análisis de varianza seguida de la prueba de Scott-knott. Las diferencias se consideraron significativas cuando P< 0,05. La FC redujo después de 20 minutos de IC y la f, PAS, PAD y PAM disminuyeron después de la inducción anestésica. Estas diferencias no fueron relevantes clínicamente y los valores se mantuvieron dentro del límite fisiológico. Se puede concluir que las dos dosis de infusión continua de fentanil produjeron estabilidad cardiovascular y respiratoria, además de permitir la disminución del requerimiento de sevoflurane para la realización de la ovariohisterectomía electiva.

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Considerando a importância da prevenção do câncer de ovário para a saúde pública e a falta de meios eficientes para o diagnóstico precoce dessa doença, esta revisão sistemática tem como objetivo avaliar o impacto da ooforectomia profilática sobre o risco de câncer de ovário. Buscamos referências bibliográficas que apresentassem associação entre a ooforectomia bilateral profilática e o câncer de ovário em pacientes sem risco aumentado para a doença em dois bancos de dados (Medline e Lilacs). Identificamos 302 artigos, mas apenas cinco foram incluídos. Somente foi encontrado um estudo em que os casos eram pacientes com ooforectomia bilateral, e o desfecho, câncer de ovário, fato que nos impediu de concluir, com base em evidências, o real papel da ooforectomia bilateral na diminuição do câncer de ovário

Considering the importance of the ovarian cancer prevention for the public health and the absence of effective techniques for the early detection of the disease, this systematic review aims at analyzing the impact of prophylactic oophorectomy on the risk of ovarian cancer. We have searched bibliographic references that studied the association between prophylactic bilateral oophorectomy and ovarian cancer in patients with average risk for this disease in two databases (Medline and Lilacs). We identified 302 articles, but only five of them were included. We only found one study in which there were patients with bilateral oophorectomy, and the outcome was ovarian cancer, what prevented us from concluding, based on evidences, the real role of bilateral oophorectomy in the reduction of ovarian cancer

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Dentre as neoplasias de origem ginecológica, o câncer de ovário continua sendo a forma mais letal e a oitava mais diagnosticada em mulheres. Sendo assim, essa patologia representa um grande desafio, pois apesar dos avanços dos métodos propedêuticos e das terapias oncológicas, a sobrevida das pacientes não se alterou nas últimas décadas. Alguns fatores como o estilo de vida, prole e principalmente a hereditariedade - encontrada em síndromes e mutações como as que envolvem os genes BRCA-1 e BRCA-2 - são responsáveis pelo aumento da predisposição ao câncer de ovário. A ooforectomia, em situações peculiares, constitui uma possibilidade de prevenção primária, apesar de suas controvérsias. O objetivo deste artigo é fazer uma revisão da literatura com análise crítica das indicações da ooforectomia profilática.

Among different types of gynecologic cancer, the ovarian cancer remains the leading form of cancer death and the eighth most prevalent in women. Thus, such pathology represents a challenge despite the propedeutic methods and oncological therapies, since survival rates have shown no changes in the past decades. Some factors such as lifestyle, offspring and mainly inheritance, which seem to be associated with deleterious mutations of BRCA-1 and BRCA-2 genes, are responsible for an increased predisposition to ovarian cancer, of which oophorectomy constitutes a dilemma concerning primary prevention. The aim of the present paper is to provide a literature review including critical analysis and indications for prophylactic oophorectomy.

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Los avances en genética hacen necesario que los médicos clínicos conozcan las implicancias y repercusiones que tiene en la vida de la mujer el ser portadora de las diferentes mutaciones de genes supresores de tumor (BRCA1 o BRCA2). Esta revisión busca la evidencia científica que ayude al consejo de las pacientes, para sugerir distintas alternativas de tratamiento, como son el seguimiento estricto y la ooforectomía profiláctica. La evidencia publicada hasta el momento, permite una adecuada guía a clínicos y pacientes, tanto en aquellas portadoras de mutaciones genéticas, como en las que solicitan consejo por dudas y temores relacionados con la aparición de cáncer de ovario. Basados en la evidencia publicada, se concluye que la ooforectomía profiláctica disminuye el riesgo de aparición de cáncer de ovario y de mama en mujeres portadoras de mutaciones en los genes BRCA1 y BRCA2.

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