PAPEL DA HIPERPROLACTINEMIA E CLORIDRATO DE PIRIDOXINA NA EXPRESSÃO DE MEDIADORES HORMONAIS NO ÚTERO DE CADELAS COM PSEUDOCIESE

A pseudociese, também conhecida como pseudogestação é caracterizada como uma síndrome, em que cadelas não castradas apresentam sinais clássicos de peri e pós-parto. Os sinais clínicos vão desde alterações comportamentais, perda de apetite, perda de peso, vômito até o sinal mais evidente que é o aumento das glândulas mamárias e secreção de leite. A secreção láctea está relacionada com a redução dos níveis de progesterona plasmática associada ao aumento de prolactina. A prolactina exerce importante papel nas funções reprodutivas, no entanto, o excesso dessa substância está associado a alterações na fertilidade tanto em animais quanto em humanos, pela inibição da kisspeptina, peptídeo essencial para a reprodução, bloqueando o eixo hipotalâmico-hipofisário-gonadal (HPG). Para o tratamento farmacológico, as substâncias mais indicadas são os inibidores de prolactina, agonistas dopaminérgicos, a cabergolina e a bromocriptina. Uma alternativa terapêutica segura, capaz de reduzir os quadros de hiperprolactinemia em cadelas pseudogestantes é a vitamina B6 (cloridrato de piridoxina). Tanto os efeitos da hiperprolactinemia quanto do cloridrato de piridoxina sobre a expressão de mediadores hormonais no útero ainda é desconhecido. Acredita-se que a infertilidade causada pela hiperprolactinemia seja, além de origem central, no eixo HPG, como também de ação periférica, particularmente no útero. Nesse sentido, objetivou-se avaliar o efeito da hiperprolactinemia e do cloridrato de piridoxina na expressão de receptores de progesterona, estrógeno, andrógeno, hormônio tireoidiano, kisspeptina e KISS-1R, através da imunohistoquímica pela técnica da estreptavidina-biotina-peroxidase no útero de cadelas pseudogestantes. Foram utilizados fragmentos uterinos de 18 cadelas, divididos em três grupos: 1) controle não tratado, 2) tratado com cloridrato de piridoxina (50 mg/kg/dia; n=6) e 3) tratado com cabergolina (5µg/kg/dia; n=6). As cadelas com pseudogestação foram tratadas por 20 dias, submetidas a cirurgia de ovário-salpingo-histerectomia e os fragmentos uterinos foram fixados em formaldeído a 10% por 24 horas e depois processados pela técnica de inclusão em parafina. Avaliou-se a expressão de marcação nas regiões de epitélio endometrial, glândulas profundas e miométrio. A expressão de receptores de progesterona é maior em glândula profunda e miométrio nos grupos tratados (P <0,05). A expressão de receptores de estrógeno e KISS-1R é fraca nas regiões uterinas em todos grupos estudados (P > 0,05). Percebe-se expressão fraca ou nula de receptores de andrógeno em glândula profunda e miométrio nos grupos tratados (P < 0,001), resposta inversa a observada para progesterona. Nota-se expressão fraca de TR no grupo tratado com piridoxina em todas as regiões uterinas (P < 0,001) e expressão fraca de kisspeptina na superfície epitelial no grupo tratado com cabergolina

Pseudocyesis, also known as pseudogestation, is characterized as a syndrome, in which non-castrated bitches show classic signs of peri and postpartum. The signs range from behavioral changes, loss of appetite, weight loss, vomiting to the most obvious sign that the mammary glands are enlarged and milk is secreted. Milk secretion is related to the reduction in plasma progesterone levels associated with increased prolactin. Prolactin plays an important role in reproductive functions, however, the excess of this substance is associated with changes in fertility in both animals and humans, by inhibiting kisspeptin, a peptide essential for reproduction, blocking the hypothalamic-pituitary-gonadal axis (HPG ) For pharmacological treatment, the most suitable substances are prolactin inhibitors, dopaminergic agonists, cabergoline and bromocriptine. A safe therapeutic alternative capable of reducing hyperprolactinemia in pseudo-pregnant dogs is a vitamin B6 (pyridoxine hydrochloride). Both the effects of hyperprolactinemia and pyridoxine hydrochloride on the expression of hormonal mediators in the uterus are still unknown. It is believed that the infertility caused by hyperprolactinemia is not only central in the HPG axis, but also of peripheral action, particularly in the uterus. In this sense, the objective was to evaluate the effect of hyperprolactinemia and pyridoxine hydrochloride on the expression of progesterone, estrogen, androgen receptors, thyroid hormone, kisspeptin and KISS-1R, through immunohistochemistry by streptavidin-biotinperoxidase in the uterus in pseudostatic bitches. Uterine fragments of 18 dogs were used, divided into three groups: 1) untreated control, 2) treated with pyridoxine hydrochloride (50 mg / kg / day; n = 6) and 3) treated with cabergoline (5µg / kg / day ; n = 6). Pseudogestation bitches were treated for 20 days, submitted to ovariansalpingo-hysterectomy surgery and the uterine fragments were fixed in 10% formaldehyde for 24 hours and then processed using the paraffin inclusion technique. Marking expression is frequent in the regions of endometrial epithelium, deep glands and myometrium. The expression of progesterone receptors is greater in the deep gland and myometrium in the treated groups (P <0.05). An expression of estrogen receptors and KISS-1R is weak in the uterine regions in all groups studied (P> 0.05). The perception of weak or null expression of androgen receptors in the deep gland and myometrium in the treated groups (P <0.001), an inverse response to that observed for progesterone. There is a weak expression of TR in the group treated with pyridoxine in all uterine regions (P <0.001) and a weak expression of kisspeptin on the epithelial surface in the group treated with cabergoline.

The role of prolactin in prostatic inflammation / O papel da prolactina na inflamação prostática

Several reports have shown that prolactin (PRL) plays a role in prostatic growth, but few studies considered the role of PRL in the process of prostatic inflammation. Young (45 ± 5 days old) and adult (75 ± 5 days old) male Wistar rats were subcutaneously injected daily with domperidone (4.0 mg.kg-1) to maintain high serum PRL levels. The animals were treated for 15, 30, 45 or 60 days. Blood and prostate samples were collected at the end of each treatment for PRL dosage and histological analysis, respectively. Only young animals treated with DOMP for 15 and 30 days displayed inflammatory infiltrate in the prostate. These results confirm literature data in regards to PRL involvement in inducing prostate inflammation. Moreover, it was concluded that young animals are more susceptible then adults to the PRL action concerning prostate inflammation(AU)

A prolactina (PRL) influencia o crescimento prostático, entretanto poucos estudos investigaram o papel da PRL na inflamação prostática. Ratos Wistar jovens (45 ± 5 dias de idade) e adultos (75 ± 5 dias de idade) receberam injeções subcutâneas diárias de domperidona (4,0 mg.kg-1) para manter níveis séricos altos de PRL. Os animais foram tratados por 15, 30, 45 ou 60 dias. Amostras de sangue e próstata foram coletadas ao final dos tratamentos para dosagem de PRL e análise histológica, respectivamente. Apenas os animais jovens tratados com domperidona por 15 e 30 dias apresentaram infiltrado inflamatório na próstata. Esses resultados confirmaram a participação da PRL na indução da inflamação prostática. A conclusão obtida foi que animais jovens são mais susceptíveis à ação da PRL na inflamação da próstata que os adultos(AU)

EFEITOS DA OLANZAPINA VIA LEITE MATERNO SOBRE O DESENVOLVIMENTO TESTICULAR DE RATOS WISTAR PRÉ-PÚBERES E SUA REPERCUSSÃO SOBRE PARÂMETROS TESTICULARES E ENDÓCRINOS EM ADULTOS

A olanzapina (OLNZ) é um antipsicótico atípico que se liga a receptores de dopamina D2 e serotonina 5HT2 amplamente prescrito para o tratamento de esquizofrenia e psicoses pós-parto. Tem sido relatada sua transferência através do leite materno para recém-nascidos. Consequentemente neonatos são susceptíveis aos seus efeitos secundários adversos. O presente estudo objetivou avaliar os efeitos da olanzapina via leite materno sobre o desenvolvimento testicular de ratos Wistar pré-púberes e sua repercussão sobre parâmetros morfométricos testiculares e endócrinos adultos. A histopatologia testicular, a análise morfométrica dos testículos, o peso de órgãos androgeno-dependentes e os níveis de prolactina e testosterona foram os parâmetros estudados. Vinte e quatro ratas prenhes (idade 3 meses) foram utilizadas neste estudo. Elas foram mantidas em quatro grupos (grupo I ao IV). Após o nascimento, quarenta e oito ratos neonatos foram distribuídos aleatoriamente para composição dos seguintes grupos: I) grupo controle solução salina NaCl 0,9% (n = 12); II) grupo tratados com 2,5 mg/kg de OLNZ (n = 12); III) grupo tratado com 5 mg/kg de OLNZ (n= 12) e IV) grupo tratado com 10 mg/kg de OLNZ (n = 12). Aos 21º dia pós-parto, os animais foram separados das respectivas mães, durante os quais o tratamento com o antipsicótico foi interrompido. Os filhotes de cada grupo foram aleatoriamente selecionados e processados para o estágio 1 do estudo: verificar o efeito da exposição antipsicótica durante a lactação sobre o desenvolvimento testicular de ratos púberes aos 21 dias de idade. A metade restante dos filhotes de cada grupo foi mantida até a idade adulta da maturidade sexual (90 dias) para o estágio 2 do estudo. No estágio 1 deste estudos, os achados histopatológicos e alterações nos parâmetros morfométricos testiculares de ratos pré-púberes, com consequente hipogonadismo, podem estar relacionados à hiperprolactinemia induzida pela OLNZ com repercussões endócrinas negativas sobre a testosterona, o que justifica a atrofia resultante do uso dessa droga durante o período crítico de desenvolvimento testicular. No estágio 2 deste estudo (90 dias), a análise histopatológica e histomorfométrica da espermatogênese indicou degeneração testicular. O hipogonadismo assim observado pode ser mediado pela hiperprolactinemia induzida por OLNZ, que inibe ainda mais a secreção de testosterona. Tal impacto adverso foi persistente até a idade adulta com doses mais elevadas do fármaco, como evidenciado pela análise do peso testicular, histologia e perfis hormonais de ratos pós-púberes expostos lactacionalmente como recém-nascidos e pubescentes. O presente estudo revelou que a exposição lactacional à olanzapina interferiu com a hipófise-gônada influenciando de forma proeminente os níveis do hormônio hipofisário prolactina que afeta adversamente os níveis de testosterona e a histopatologia testicular.

Olanzapine (OLNZ) is an atypical antipsychotic that binds to dopamine (D2) and serotonin (5HT2) receptors, widely prescribed for the treatment of schizophrenia and postpartum psychosis. Its transfer through breast milk to newborns has been reported. Consequently, neonates are susceptible to their adverse side effects. In the present study, aims to evaluate the effects of OLNZ administered through breast milk on the testicular development of newborn rats exposed to lactation. The testicular histopathology, the morphometric analysis of the testes, androgen-dependent organs weights and the levels of prolactin and testosterone were the several end points studied. Twenty-four pregnant rats (age 34 months) and their pups were used in this study. After birth, forty-eight pup rats were randomly assigned to the following groups: I) control group saline solution NaCl 0.9% (n = 12), II) treated group with 2.5 mg/kg OLNZ (n = 12), III) treated group with 5 mg/kg (n = 12) and IV) treated group with 10 mg/kg of OLNZ (n = 6). Each mother along with their pups was housed singly in PVC cages. On the 21st day postpartum, the animals were separated from their respective mothers, during which treatment with the antipsychotic was stopped. The pubent rats of each group were randomly selected and processed for stage 1 of the study: to verify the effect of antipsychotic exposure during lactation on the testicular development of pubertal rats at 21 days of age. The remaining half of the male offspring of each group were maintained until adulthood of sexual maturity (90 days) for stage 2 of the study. At stage 1 of this study, Histopathological findings, and changes in testicular morphometric parameters of pubescent rats, with consequent hypogonadism, may be related to OLNZ-induced hyperprolactinemia with negative endocrine repercussions on testosterone, which justifies the atrophy resulting from the use of OLNZ during the critical period of testicular development. At stage 2 of the study (90 days), the histopathologic and histomorphometric analysis of spermatogenesis indicated testicular degeneration. The hypogonadism thus observed might be mediated by OLNZ-induced hyperprolactinemia, which further inhibited secretion of testosterone. Testicular degenerative processes associated with hormonal changes in adult rats have a significance for this irreversible event even after discontinuation of the antipsychotic after weaning. Thus, adverse impact was persistent until adulthood with higher doses of the drug as evidenced by the analysis of testicular weight, histology and hormonal profiles of post-pubertal rat lactationally exposed as neonates and pubescents. The present study thus revealed that the lactational exposure to OLNZ interfered with the pituitary testicular axis by prominently influencing blood levels of pituitary hormone prolactin and adversely affecting testosterone levels and testicular histopathology.

Mammary gland carcinosarcoma in a New Zealand white rabbit (Oryctolagus cuniculus)

Background: Carcinosarcoma of the breast (metaplastic, biphasic metaplastic, metaplastic sarcomatoid carcinoma, sarcomatoid carcinoma) is an aggressive, rare neoplasm that has been reported to account for 0.08-0.2% of all breast malignancies. Mammary carcinosarcoma is rare in rabbits. Carcinosarcoma is a neoplasia composed of cells morphologically resembling malignant epithelial components and cells resembling malignant connective tissue elements. In spite of the rarity in rabbits, carcinosarcoma should always be considered in the different diagnoses of the mammary neoplasias, especially those of undifferentiated neoplasias. Case: An eight-month-old, female New Zealand white rabbit (Oryctolagus cuniculus) weighing 1.9 kg was referred to Tabriz university veterinary hospital for acute swelling on the abdomen and history of mammary mass. The complete blood count was within the reference ranges. The rabbit had been slightly depressed and anorectic. At clinical examination, the patient presented a huge lobulated mass in the mammary gland area. Clinical signs were included: emaciation and hardness in moving. Due to unfavorable prognosis the rabbit was euthanized and afterward complete mastectomy was performed. At necropsy, a non-infiltrative multilobulated mass were observed in the chirurgic area. The mass didn't infiltrate into the skin, subcutaneously and adjacent to the musculature and it was moved easily. The neoplasia was solid, firm, and yellowbrownish. Tissue samples of the tumor were fixed in 10% neutral buffered formalin, embedded in paraffin, cut at 5 µm, and stained with hematoxylin and eosin and masson trichrome. Microscopically, the neoplasm had a solid pattern and was composed of a heterogeneous cell population, mainly pleomorphics. Polyhedral cells showing ovoid or vesicular nuclei with prominent nucleoli and abundant lightly acidophilic cytoplasm resembling epithelial cells were observed. Cells with scant cytoplasm and elongated or oval nuclei containing inconspicuous nucleoli resembling mesenchymal cell were also observed. There were also neoplastic areas with a myxoide matrix. Some young cartilage pieces were observed in the tumor. In some parts of the tumor a very dense fibrous connective tissue was observed. Based on the histological findings, the diagnosis of mammary carcinosarcoma was confirmed. Other organs showed normal histological characteristics. Discussion: The carcinosarcoma is a neoplasia characterized as containing a mixed cell population with malignant proliferation of both mesenchymal and epithelial-like cells. Although the carcinosarcoma is rare in the domestic species, their origin has been discussed in two theories: 1) multiclonal theory suggests that the epithelial and the mesenchymal components originated from two or more stem cells; 2) the monoclonal theory suggests that the epithelial and the mesenchymal components originated from totipotential neoplastic cells play multiple potential pathways of terminal differentiation. Abnormal level of growth and Prolactin hormones is one cause to breast tumors. Recent evidence supports the speculation that prolonged hyperprolactinemia leads to malignancy, given the case of ductal carcinoma in one woman who, after incomplete pituitary adenomectomy, was hyperprolactinemic for 15 years. This physiologic relationship and disease progression are important to consider in clinical diagnosis and management of these cases in rabbits. Although some studies were not showed any difference in level of mentioned hormones. In spite of being rare in rabbit, the carcinosarcoma should always be considered in the different diagnoses of the mammary neoplasias, mainly of those undifferentiated neoplasias.

Caracterização genotípica de Arcobacter spp. isolados de carnes de aves comercializadas no Município de São Paulo - SP

Foi investigada a hipótese da hiperprolactinemia modular a resposta inflamatória alérgica pulmonar em ratos machos e em fêmas lactantes sem tratamento de domperidona. Métodos: Em ratos machos, a hiperprolactinemia foi de curta duração (5 dias) induzida pela domperidona (5,1 mg.kg-1 por dia, i.p). A resposta alérgica foi gerada por sensibilização e desafios inalatórios com ovoalbumina. Foi feita contagem de leucócitos totais e diferenciados do lavado bronco alveolar (BAL), lavado medular femoral (BFL) e sangue; a percentagem de produção de muco e colageno no pulmão, níveis de corticosterona e prolactina e citocinas TNF-, IL-4, IL-6, IL-10, em explantes de pulmão e IFNg no BAL, foram medidos. Pela citometria foram avaliadaos os receptores de prolactina; Resultados: Hiperprolactinemia de curta duração feita antes do desafio inalatório disminuiu a resposta alérgica pulmonar na contagem de leucócitos no lavado broncoalveolar. Esse tratamento reduziu a celularidade no BFL e a percentagem de muco e aumentou a expressão de citocinas IL-4, IL-6, IL-10, TNF e da expressão do IFNg. Níveis altos de prolactina diminuiram o número de eosinófilos ao pulmão no BAL. Pela citometria revelou-se que além de ter menor número de granulócitos migrados ao pulmão, estes apresentaram maior expressão do número de receptores por granulócito para prolactina no grupo tratado com domperidona. Alterações similares foram reveladas em fêmeas lactantes como foi a diminuição nos leucócitos do BAL, e no número de células do BFL. O tratamento profilático diminuiu a resposta alérgica tanto no grupo hiperprolactinêmico como no grupo veículo. O tratamento feito após o desafio inalatório não evidenciou alterações relevantes nas variáveis medidas. Conclusões: A hiperprolactinemia de curta duração, feita após a sensibilização e antes da inalação diminui a resposta inflamatória no pulmão em ratos. Os resultados deste estudo demonstram que a hiperprolactinemia induzida antes do desafio antigênico diminue a inflamação alérgica pulmonar. Assim, é provável que a prolactina endógena tenha um papel relevante como um imunomodulador da asma. Este estudo aponta a possibilidade futura do uso da domperidona para pacientes asmáticos. Durante a primavera muitas espécies de mamíferos têm seus filhotes e ocorre abundância de fatores alergenos no ar. Logo, um fator endógeno que favoreça a proteção de fêmeas durante a lactação, tal como a hiperprolactinemia, tem elevado valor adaptativo.

It was investigated if hyperprolactinemia has modulatory actions on lung allergic inflammatory response in male rats. Lactating female rats were tested for pulmonary allergy as well. Methods: In male rats, short-term (5 days) hyperprolactinemia was induced by domperidone (5.1 mg.kg-1 per day, ip). Allergic response was generated by sensitization and inhalation challenge with ovalbumin. Total and differential leukocytes bronchoalveolar lavage (BAL), femoral medullary lavage (BFL) and blood; the percentage of collagen and mucus production in the lungs, plasma levels of corticosterone and prolactin cytokines and TNF-, IL-4, IL-6, IL-10, IFNg explants lung and BAL, were measured. Flow cytometry was used to evaluate prolactin receptor; Results: Short-term hyperprolactinemia made before the inhaled challenge reduced the pulmonary allergic response in white blood cell counts in BAL. This treatment reduced the cellularity in BFL and the percentage of mucus and increased expression of cytokines IL-4, IL-6, IL-10, TNFa and IFNg expression. High prolactin levels decreased the number of eosinophils to the lung in BAL. There were fewer granulocytes migrated to the lung. These granulocytes showed higher expression prolactin receptors in hyperprolactinemia animals. Similar changes were revealed in lactating females. In these animals, there was a reduction in BAL leukocyte, and the number of cells BFL. Prophylactic treatment decreased the allergic response in both hyperprolactinemic and vehicle groups. The treatment made after inhalational challenge did not induce significant changes in the variables measured in this study. Conclusions: Short-term hyperprolactinemia, made after sensitization and before inhalation, decreases the inflammatory response in the lung of rats. The results of this study demonstrate that hyperprolactinemia, induced before antigen challenge, decreases pulmonary allergic inflammation. Thus, it is probable that the endogenous prolactin has an important role as an immunomodulator of asthma. This study points out the prospect of a future use of domperidone for asthmatic patients. For various mammalian species, parturition occurs during springtime. Pollen in the air might be an abundant allergic factor during springtime. Thus, protecting lactating females against this type allergy might have high adaptive value.