Vacuolização neuronal e degeneração espinocerebelar em filhote de Rottweiler / Neuronal vacuolation and spinocerebellar degeneration in a Rottweiller puppy

Background: Spinocerebellar degenerations and neuronal vacuolations are alterations characterized by the formation of vacuoles in the nervous tissue, commonly called status spongiosus. This condition occurs in young Rottweiler dogs causing a disease called Neuronal Vacuolation and Spinocerebellar Degeneration. Clinically, it presents with ataxia of the pelvic limbs, which evolves to generalized ataxia, tetraparesis, and laryngeal paralysis. Histologically, spongiform and vacuolar alterations of the neuropil and neurons are highlighted. This reports a case of neuronal vacuolation and spinocerebellar degeneration in a Rottweiler puppy. Case: Necropsy was performed on the cadaver of a 5-month-old Rottweiler bitch that had been presenting with ataxia for approximately 1 month, in addition to dyspnea, pulmonary crepitations, and microphthalmia. Macroscopic evaluation revealed pale ocular and oral mucosae; marked gastric dilatation and abdominal distension; pulmonary hemorrhage and edema; hepatosplenomegaly; fatty degeneration of the liver; and congestion of meningeal blood vessels. Microscopically, histological evaluation of the spinal cord showed an increase in gray matter cellularity with marked presence of oligodendrocytes and microglia cells; moderate to severe multifocal intracytoplasmic micro- and macrovacuoles with displacement of the neurons' nuclei to the periphery of the cell; central chromatolysis of the neurons adjacent to neurons affected by vacuolation; and mild multifocal necrosis associated with mild multifocal neuronophagia. The white matter exhibited discrete digestion chambers, in addition to marked diffuse congestion of the leptomeninges. In the cerebellum, neurons in the nerve nuclei (emboliform, globose, and fastigial) showed moderate multifocal vacuoles in the cytoplasm, whereas adjacent neurons showed central chromatolysis, necrosis, and mild neuronophagia. Additional histological findings included lymphoid hyperplasia, fatty degeneration of the liver, pulmonary edema, and pulmonary hemorrhage. Discussion: Spongiform and degenerative encephalopathies are diseases recognized worldwide, mainly in cattle and sheep. However, the identification of these changes in new species has led to the need for further investigations. In dogs, the first reports occurred in 1995 and 1997 in Rottweiler animals. This disease affects young dogs, and although its pathogenesis is not completely known, it is believed to be associated with a genetic mutation in the RAB3GAP1 gene. Clinically, it is associated with clinical neurological manifestations, including progressive ataxia of the pelvic limbs, changes in spinal reflex, disordered proprioceptive reactions, laryngeal paralysis, as well as behavioral and gait alterations. In the clinical evaluation, leukoencephalomyelopathy and neuroaxonal dystrophy should be diseases considered as possible differential diagnoses, as they present with similar alterations. However, in histological evaluation, the exclusion of both is basically due to the absence of neuronal vacuolization. Unfortunately, the definitive diagnosis is only made post mortem, through a histopathological evaluation of the nervous tissue. Because it is a disease whose pathogenesis is little known and which shows signs of having a genetic character, histopathological examination for diagnostic purposes in young animals with neurological signs is of great importance.

Evidence of pituitary hypoplasia associated with partial central diabetes insipidus in a young Persian cat

Background: Congenital anomalies are an uncommon pituitary hypofunction cause associated to multiple hormone deficiencies. Congenital hyposomatotropism is often related to an inherited anomaly, characterized mainly by delayed growth. It is not uncommon to find associated thyroid-stimulating hormone and gonadotropin deficiencies. Pituitary malformation may be associated to progressive cystic lesion expansion. Central diabetes insipidus (CDI) is another rare disease associated to polyuria (PU) and polydipsia (PD) secondary to antidiuretic hormone (ADH) deficient secretion. The aim of this report is to describe a likely case of pituitary hypoplasia, associated with partial CDI in a cat. Case: A 9-month-old unneutered male Persian cat weighing 2 kg was presented due to severe polyuria and polydipsia associated with growth deficit when compared with its sibling. After clinical and laboratory evaluations during the months in which the patient was monitored, reduced serum concentration of insulin-like growth factor-1 (IGF-1), thyroid-stimulating hormone (TSH), thyroid hormones, and testosterone were documented, confirming the diagnosis of hyposomatotropism, hypogonadism, and secondary hypothyroidism. Furthermore, therapeutic diagnosis with desmopressin revealed partial central diabetes insipidus (CDI). As the sibling showed normal development aging 13-months, a radiographic examination of the forelimb (carpus) was performed on both cats. There was lack of growth plate fusion in the patient, without any other evidence of dysgenesis, whereas complete epiphyseal closure was observed in the sibling. Despite therapeutic prescriptions of desmopressin and levothyroxine, the owners refused further follow-up to the...

Evidence of pituitary hypoplasia associated with partial central diabetes insipidus in a young Persian cat

Background: Congenital anomalies are an uncommon pituitary hypofunction cause associated to multiple hormone deficiencies. Congenital hyposomatotropism is often related to an inherited anomaly, characterized mainly by delayed growth. It is not uncommon to find associated thyroid-stimulating hormone and gonadotropin deficiencies. Pituitary malformation may be associated to progressive cystic lesion expansion. Central diabetes insipidus (CDI) is another rare disease associated to polyuria (PU) and polydipsia (PD) secondary to antidiuretic hormone (ADH) deficient secretion. The aim of this report is to describe a likely case of pituitary hypoplasia, associated with partial CDI in a cat. Case: A 9-month-old unneutered male Persian cat weighing 2 kg was presented due to severe polyuria and polydipsia associated with growth deficit when compared with its sibling. After clinical and laboratory evaluations during the months in which the patient was monitored, reduced serum concentration of insulin-like growth factor-1 (IGF-1), thyroid-stimulating hormone (TSH), thyroid hormones, and testosterone were documented, confirming the diagnosis of hyposomatotropism, hypogonadism, and secondary hypothyroidism. Furthermore, therapeutic diagnosis with desmopressin revealed partial central diabetes insipidus (CDI). As the sibling showed normal development aging 13-months, a radiographic examination of the forelimb (carpus) was performed on both cats. There was lack of growth plate fusion in the patient, without any other evidence of dysgenesis, whereas complete epiphyseal closure was observed in the sibling. Despite therapeutic prescriptions of desmopressin and levothyroxine, the owners refused further follow-up to the...(AU)

Infecção de trato urinário inferior por Citrobacter sp em cadela com hipoadrenocorticismo / Citrobacter sp lower urinary tract infection in a bitch with hypoadrenocorticism

Citrobacter sp. é um microrganismo frequentemente encontrado em vagina de cadelas, mas corresponde a menos de 3% do total de microrganismos isolados em urocultura. O hipoadrenocorticismo (HA) é uma doença endócrina incomum e que leva a poliúria e hipostenúria. O objetivo deste trabalho é relatar o caso de uma fêmea da espécie canina, da raça Teckel, 11 anos, atendida com queixa de urina de odor alterado há vários dias, além de vômito, diarreia e inapetência há três dias, e poliúria e polidipsia há 2 meses, com histórico de tratamento anterior com mitotano para hiperadrenocorticismo. O diagnóstico foi de ITU por Citrobacter sp., além de HA iatrogênico. Como destaques nos exames, relação sódio:potássio de 22,6 foi observada, sugestiva de HA, que foi confirmado por teste de estimulação com ACTH, além de urina inicialmente hipostenúrica (densidade 1,006), o que pode ser atribuído ao washout medular renal devido à hiponatremia causada pelo hipoadrenocorticismo. O tratamento foi feito com amoxicilina associada a ácido clavulânico por 20 dias, além da terapia específica para HA com prednisona e fludrocortisona, que foi continuado. A paciente recuperou-se bem, a densidade urinária aumentou após início do tratamento para HA e não houve recidiva da ITU em período de acompanhamento de 8 meses. Acredita-se que a baixa densidade urinária causada pelo HA tenha sido fator essencial para a oco

Citrobacter sp. is a normal constituent of bitches vagina, but it is related to less than 3% of total isolated microorganism in uroculture. Hypoadrenocorticism (HA) is an endocrine disease uncommonly diagnosed that leads to polyuria and hypostenuria. The aim of this work is report the case of a Teckel bitch, 11 years old, attended with complaint of altered urinary smell for several days, besides vomiting, diarrhea and inappetence for three days, and polyuria and polydispsia for two months, with previous mitotane treatment for hyperadrenocorticism. The diagnosis was Citrobacter UTI, besides iatrogenic HA. The most important exam results include sodium:potassium ratio of 22.6, suggestive of HA, that was confirmed by ACTH stimulation test. Besides, hypostenuria (urinary specific gravity USG - of 1.006) was noted, attributed to renal medular washout due to hyponatremia seen in HA. Therapy comprised amoxicillin associated with clavulanic acid for 20 days, in addition to specific therapy for AH with prednisone and fludrocortisone. The patient recovery well, USG increased after the beginning of the treatment for HA and there was no UTI reinfection for a 8 month period. It is believed that low USG due to HA was essential for the occurrence of Citrobacter UTI.(AU)

Infecção de trato urinário inferior por Citrobacter sp em cadela com hipoadrenocorticismo / Citrobacter sp lower urinary tract infection in a bitch with hypoadrenocorticism

Citrobacter sp. é um microrganismo frequentemente encontrado em vagina de cadelas, mas corresponde a menos de 3% do total de microrganismos isolados em urocultura. O hipoadrenocorticismo (HA) é uma doença endócrina incomum e que leva a poliúria e hipostenúria. O objetivo deste trabalho é relatar o caso de uma fêmea da espécie canina, da raça Teckel, 11 anos, atendida com queixa de urina de odor alterado há vários dias, além de vômito, diarreia e inapetência há três dias, e poliúria e polidipsia há 2 meses, com histórico de tratamento anterior com mitotano para hiperadrenocorticismo. O diagnóstico foi de ITU por Citrobacter sp., além de HA iatrogênico. Como destaques nos exames, relação sódio:potássio de 22,6 foi observada, sugestiva de HA, que foi confirmado por teste de estimulação com ACTH, além de urina inicialmente hipostenúrica (densidade 1,006), o que pode ser atribuído ao washout medular renal devido à hiponatremia causada pelo hipoadrenocorticismo. O tratamento foi feito com amoxicilina associada a ácido clavulânico por 20 dias, além da terapia específica para HA com prednisona e fludrocortisona, que foi continuado. A paciente recuperou-se bem, a densidade urinária aumentou após início do tratamento para HA e não houve recidiva da ITU em período de acompanhamento de 8 meses. Acredita-se que a baixa densidade urinária causada pelo HA tenha sido fator essencial para a oco

Citrobacter sp. is a normal constituent of bitches’ vagina, but it is related to less than 3% of total isolated microorganism in uroculture. Hypoadrenocorticism (HA) is an endocrine disease uncommonly diagnosed that leads to polyuria and hypostenuria. The aim of this work is report the case of a Teckel bitch, 11 years old, attended with complaint of altered urinary smell for several days, besides vomiting, diarrhea and inappetence for three days, and polyuria and polydispsia for two months, with previous mitotane treatment for hyperadrenocorticism. The diagnosis was Citrobacter UTI, besides iatrogenic HA. The most important exam results include sodium:potassium ratio of 22.6, suggestive of HA, that was confirmed by ACTH stimulation test. Besides, hypostenuria (urinary specific gravity – USG - of 1.006) was noted, attributed to renal medular washout due to hyponatremia seen in HA. Therapy comprised amoxicillin associated with clavulanic acid for 20 days, in addition to specific therapy for AH with prednisone and fludrocortisone. The patient recovery well, USG increased after the beginning of the treatment for HA and there was no UTI reinfection for a 8 month period. It is believed that low USG due to HA was essential for the occurrence of Citrobacter UTI.

Numeric and volumetric changes in Leydig cells during aging of rats

Purpose: To analyze the effects of aging in rats on the nuclear volume, cytoplasmic volume, and total volume of Leydig cells, as well as their number. Methods: Seventy-two Wistar rats were divided into six subgroups of 12 rats, which underwent right orchiectomy at 3, 6, 9, 12, 18, and 24 months of age. The weight and volume of the resected testicles were assessed. A stereological study of Leydig cells was conducted, which included measurements of cell number and nuclear, cytoplasmic, and total cell volumes. Results: The weight and volume of the resected testicles showed reductions with age. Only the subgroup composed of 24-month old rats showed a decrease in the nuclear volume of Leydig cells. Significant reductions in the cytoplasmic volume and total volume of Leydig cells were observed in 18- and 24-month old rats. The number of Leydig cells did not vary significantly with age. Conclusions: Aging in rats resulted in reduction of the nuclear, cytoplasmic, and total cell volumes of Leydig cells. There was no change in the total number of these cells during aging.(AU)

AVALIAÇÃO DO SISTEMA KISS-KISS1R NO SISTEMA GENITAL DE GATAS HÍGIDAS E COM PIOMETRA E SUA RELAÇÃO COM A EXPRESSÃO DE MEDIADORES ANGIOGÊNICOS E IMUNOLÓGICOS

A kisspeptina (Kp) é um neuropeptídeo codificado pelo gene Kiss1 que estimula a liberação hipotalâmica de GnRH via seu receptor Kiss1R. Falhas na sua expressão resulta em hipogonadismo hipogonadotrófico em humanos e animais e por isso ela tem sido considerada o peptídeo chave da reprodução. No entanto, falhas na sinalização periférica de Kp, principalmente no sistema genital, também causa infertilidade. Contudo, estudos sobre o perfil de expressão do sistema Kiss-Kiss1R no sistema genital e sua relação com mediadores imunológicos e angiogênicos em condições fisiológicas e patológicas são ainda escassos, principalmente na gata doméstica que não há nenhum estudo. Nesse sentido, este estudo teve como objetivo avaliar o perfil de expressão de Kp e seu receptor (Kiss1R) no útero, ovário e placenta de gatas (Felis catus) hígidas e com piometra e sua relação com a expressão de fatores pró-angiogênicos (VEGF, Flk-1 e PIGF) e imunológicos (INF, MIF, TNF, IL6 e IL10). Para isso, o trabalho foi realizado em três etapas: no CAPITULO 1 avaliou-se a expressão do sistema Kiss-Kiss1R e dos mediadores angiogênicos e imunológicos no útero de gatas ao longo do ciclo estral e na condição de piometra; no CAPÍTULO 2 avaliou-se a influência da gestação na expressão uterina do sistema Kiss-Kiss1R e dos mediadores angiogênicos e imunológicos, como também o perfil de expressão na interface materno-fetal ao longo da gestação; e no CAPÍTULO 3 avaliou-se o perfil do sistema Kiss-Kiss1R e dos mediadores angiogênicos e imunológicos durante a foliculogênese, luteogênese e regressão luteal de gatas cíclicas e gestantes. Para o estudo foram utilizados 109 animais divididos nos grupos proestro/estro (N=20), diestro (N=41), anestro (N=32), piometra (N=4) e gestantes (N=12) após avaliação clínica, histopatológica e dosagem hormonal de estradiol (E2) e progesterona (P4) (CEUA 005/18). As amostras de útero, placenta e ovário foram avaliados quanto a expressão de Kiss, Kiss1R, VEGF, Flk-1, PIGF, INF, MIF, TNF, IL6 e IL10 por meio de imunohistoquimica e qPCR. Os dados foram analisados por ANOVA seguido do teste StudentNewmanKeuls (SNK) ou teste t de Student. Em relação ao ciclo estral, foi verificado que o útero de gatas em diestro apresenta maior expressão gênica e proteica de Kiss, como também maior expressão de fatores pró-angiogênicos e de Mif e Il6 (P<0,05). Em contrapartida, Kiss1R apresentou maior expressão uterina na fase de proestro/estro, semelhante ao observado para a imunomarcação dos fatores inflamatórios (P<0,05). Para a maioria desses fatores houve correlação gênica significativa e positiva com a expressão uterina de Kiss e/ou Kiss1r, além de ter ocorrido correlação gênica positiva entre Kiss e seu receptor no útero de gatas ao longo do ciclo estral (P<0,05). Gatas com piometra apresentaram aumento da expressão uterina de Kiss e Kiss1R (P<0,05), enquanto ocorreu redução significativa da expressão de RNAm para Vegf, Pigf, Mif e Il6, e aumento da expressão de Tnf. Em relação à interface materno-fetal, a gestação em gatas aumenta a expressão uterina de Kiss e Kiss1r , principalmente no final da gestação, além de aumentar a expressão endometrial de MIF, Vegf, Il10 e Tnf (P<0,05), diferente de Pigf que apresentou redução da expressão gênica (P<0,05). Na placenta, o sistema KissKiss1R foi expresso no meio e final da gestação, com maior expressão gênica de Kiss1r ao final da gestação. A expressão gênica e/ou proteica placentária de VEGF, Flk-1, INFy, TNF, IL6 e IL10 foi maior no meio da gestação (P<0,05), diferente de Pigf que apresentou maior expressão de RNAm no final da gestação (P<0,05). Além disso, na placenta houve correlação gênica positiva entre Kiss e Tnf, e negativa entre Kiss1r e Inf, Il6 e Il10 (P<0,05), embora não tenha ocorrido correlação significativa entre Kiss e seu receptor (P>0,05). Em relação ao ovário, expressão moderada a intensa de Kiss e dos mediadores angiogênicos e imunológicos foi observada em todos os folículos, enquanto Kiss1R apresentou expressão fraca e principalmente em folículos primordiais. Na luteogênese, a gestação aumentou a expressão luteal de Kiss, como também houve maior imunomarcação em corpos lúteos (CLs) maduros de gatas gestantes e não gestantes. Kiss1R, entretanto, apresentou maior expressão proteica somente nos CLs maduros de gatas gestantes (P<0,05). A expressão proteica de MIF foi maior em CLs maduros de gatas gestantes e não gestantes em relação aos CLs vacuolizados e corpos albicans (P<0,05), enquanto a gestação reduziu a expressão gênica luteal de Mif (P<0,05). Os corpos albicans apresentaram menor expressão de Kiss, Kiss1r, Vegf e Mif em relação aos CLs de animais gestantes e não gestantes. Conclui-se que o sistema Kiss/Kiss1R é expresso no útero, ovário e placenta da gata doméstica, sendo que o perfil de expressão do mesmo sofre influência não somente do ciclo estral, com maior expressão durante o diestro, como também da gestação, que modulou positivamente a expressão uterina e luteal de Kiss e/ou Kiss1R. Além disso, a expressão de Kiss/Kiss1r apresenta correlação gênica com a expressão de mediadores angiogênicos e imunológicos no sistema genital da gata doméstica, sendo que os mesmos variam o seu perfil de expressão de acordo com a fase do ciclo estral e o estágio luteal e gestacional.

Kisspeptin (Kp) is a neuropeptide encoded by the Kiss1 gene that stimulates the hypothalamic release of GnRH via its Kiss1R receptor. Failures in its expression results in hypogonadotrophic hypogonadism in humans and animals and has therefore been considered the key peptide of reproduction. However, failures in peripheral Kp signaling, especially in the genital system, also cause infertility. However, studies on the expression profile of the Kiss/Kiss1R system in the genital system and its relationship with immunological and angiogenic mediators in physiological and pathological conditions are still scarce, especially in the domestic cat that there is no study. In this sense, this study aimed to evaluate the expression profile of Kp and its receptor (Kiss1R) in the uterus, ovary and placenta of healthy cats (Felis catus) and with pyometra and its relationship with the expression of pro-angiogenic (VEGF, Flk-1, and PIGF) and immunological (INF, MIF, TNF, IL6, and IL10) factors. For this, the work was carried out in three stages: in CHAPTER 1, the expression of the Kiss / Kiss1R system and of the angiogenic and immunological mediators in the uterus of cats throughout the estrous cycle and in the condition of pyometra was evaluated; in CHAPTER 2, the influence of pregnancy on the uterine expression of the Kiss/Kiss1R system and of the angiogenic and immunological mediators was evaluated, as well as the expression profile in the maternal-fetal interface throughout pregnancy; and in CHAPTER 3, the profile of the Kiss / Kiss1R system and of the angiogenic and immunological mediators during folliculogenesis, luteogenesis and luteal regression of cyclical and pregnant cats was evaluated. For the study, 109 animals were used and divided into the groups of proestrus/estrus (N = 20), diestrus (N = 41), anestrus (N = 32), pyometra (N = 4) and pregnant (N = 12) after clinical and histopathological evaluation and hormonal dosage of estradiol (E2) and progesterone (P4) (CEUA 005/18). The uterus, placenta and ovary samples were evaluated for the expression of Kiss, Kiss1R, VEGF, Flk-1, PIGF, INF, MIF, TNF, IL6 and IL10 by immunohistochemistry and qPCR. The data were analyzed by ANOVA followed by the Student Newman Keuls test (SNK) or Student t test. In relation to the estrous cycle, it was found that the uterus from cats in diestrus has higher gene and protein expression of Kiss, as well as higher expression of pro-angiogenic factors and Mif and Il6 (P <0.05). In contrast, Kiss1R showed higher uterine expression in the proestrus / estrus phase, similar to that observed for the immunostaining of inflammatory factors (P <0.05). For most of these factors there was a significant and positive gene correlation with the uterine expression of Kiss and / or Kiss1r, in addition to the positive gene correlation between Kiss and its receptor in the uterus from cats throughout the estrous cycle (P <0.05). Cats with pyometra showed higher uterine expression of Kiss and Kiss1R (P <0.05), while there was a significant reduction in mRNA expression for Vegf, Pigf, Mif and Il6, and increased expression of Tnf. In relation to the maternalfetal interface, pregnancy in cats increases the uterine expression of Kiss and Kiss1r, especially at the end of pregnancy, in addition to increasing the endometrial expression of MIF, Vegf, Il10 and Tnf (P <0.05), differently of Pigf that showed reduced gene expression (P <0.05). In the placenta, the Kiss-Kiss1R system was expressed in the middle and end of pregnancy, with higher Kiss1r gene expression at the end of pregnancy. Placental gene and/or protein expression of VEGF, Flk-1, INFy, TNF, IL6 and IL10 was higher in the middle of pregnancy (P <0.05), unlike Pigf which showed higher mRNA expression at the end of pregnancy (P <0.05). Furthermore, in the placenta there was a positive gene correlation between Kiss and Tnf, and negative between Kiss1r and Inf, Il6 and Il10 (P <0.05), although there was no significant correlation between Kiss and its receptor (P> 0.05). In relation to the ovary, moderate to intense expression of Kiss and of the angiogenic and immunological mediators was observed in all follicles, while Kiss1R showed weak expression and mainly in primordial follicles. In luteogenesis, pregnancy increased Kiss luteal expression, as well as higher immunostaining in mature corpus luteum (CLs) from pregnant and non-pregnant cats. Kiss1R, however, showed higher protein expression only in the mature CLs of pregnant cats (P <0.05). MIF protein expression was higher in mature CLs of pregnant and non-pregnant cats compared to vacuolated CLs and corpus albicans (P <0.05), while pregnancy reduced the luteal gene expression of Mif (P <0.05). Corpus albicans showed lower expression of Kiss, Kiss1r, Vegf and Mif in relation to CLs from pregnant and non-pregnant animals. It is concluded that the Kiss-Kiss1R system is expressed in the uterus, ovary and placenta of the domestic cat, and its expression profile is influenced not only by the estrous cycle, with higher expression during diestrus, but also during pregnancy, which positively modulated the uterine and luteal expression of Kiss and/or Kiss1R. In addition, the Kiss-Kiss1r expression has gene correlation with the expression of angiogenic and immunological mediators in the genital system of the domestic cat, and they vary their expression profile according to the estrous cycle phase and the luteal and gestational stage.

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.

Resposta da paratireóide de ratas às variações do cálcio e fósforo plasmáticos no hipertireoidismo e hipogonadismo / Response of parathyroid to the plasmatic of calcium and phosphorus variations in hyperthyroidism and hypogonadism in the rat

Foram estudadas 84 paratireóides de ratas Wistar com cinco meses de idade, castradas ou não, e mantidas em hipertireoidismo por períodos de 30, 60 e 90 dias. Dois grupos eutireóideos, um castrado e o outro não, foram mantidos nas mesmas condições e serviram de controle. Ao final de cada período, foram colhidos o plasma, para determinação da concentração de T4 livre, o cálcio e o fósforo e as paratireóides, para análise morfológica e determinação da porcentagem de núcleo, citoplasma e estroma. Aos 90 dias houve reversão da hipocalcemia observada aos 60 dias nos animais eutireóideos castrados e não castrados, graças à hipertrofia da paratireóide. O mesmo não ocorreu com os grupos hipertireóideos que apresentaram hipocalcemia e hiperfosfatemia progressivas e não compensadas até os 90 dias. Na castração há pronta reversão da hipocalcemia em resposta ao aumento da atividade funcional da paratireóide. No estado hipertireóideo com gônadas funcionais, apesar da hipertrofia da paratireóide, não há retorno à isocalcemia e isofosfatemia. Na associação hipertireoidismo-castração, a paratireóide não responde satisfatoriamente à hipocalcemia e hiperfosfatemia intensas e progressivas.(AU)

Eighty four parathyroids of castrated and intact adult female Wistar rats kept under hyperthyroidism state for 30, 60 or 90 days were studied. Two euthyroid goups, one castrated and another intact were used as controls. At the end of each period, blood was collected and the concentrations of free T4, calcium and phosphorus were determined. The parathyroids were analysed microscopically and % of nuclei, cytoplasm and stroma were determined. Hypocalcemia that was observed in castrated and intact euthyroid rats at 60 days was reverted after 90 days due to parathyroid hypertrophy. In hyperthyroid groups, hypocalcemia and hyperphosphatemia were progressive and did not revert at 90 days. In conclusion, castration revert hypocalcemia due to the increase of parathyroid activity. In spite of parathyroid hypertrophy, hyperthyroid state with functional gonads did not return to isocalcemia and isophosphatemia state. In addition, under the association of hyperthyroidism-castration, parathyroid did not respond to progressive hypocalcemia and hyperphosphatemia.(AU)

Relação tireóide-gônadas e níveis plasmáticos de fósforo, cálcio e fosfatase alcalina em ratas

The interrelation between thyroid, gonads and osseous metabolism was studied in either intact or castrated adult female rats kept under hyperthyroidism or euthyroidism for 30, 60, or 90 days. Plasmatic levels of phosphorus, calcium, and alkaline phosphatase were measured to assess the osseous metabolism. These characteristics were correlated to the levels of estrogen, progesterone, and free T4. Either hypogonadism or hyperthyroidism interfered with the plasmatic characteristics of osseous metabolism. Hyperphosphatemia and hypocalcemia were induced by hyperthyroidism, whereas the hypogonadism had little effect on the levels of phosphorus, but it had a potencialization effect on the hyperphosphatemia and hypocalcemia induced by hyperthyroidism. The effect of hypogonadism on the alkaline phosphatase activity was reduced by the hyperthyroidism.

A relação tireóide-gônadas-metabolismo ósseo foi estudada em ratas Wistar adultas, castradas ou intactas e mantidas em estado hipertireóideo ou eutireóideo por períodos de 30, 60 e 90 dias. Foram utilizadas como características do metabolismo ósseo o cálcio, o fósforo e a atividade da fosfatase alcalina plasmáticos, correlacionando-os com os valores de estrógeno, de progesterona e de T4 livre. Verificou-se que o hipogonadismo e o hipertireoidismo alteram as características plasmáticas do metabolismo ósseo. O hipertireoidismo induz hiperfosfatemia e hipocalcemia, o hipogonadismo tem pouca influência sobre o fósforo, mas potencializa a hiperfosfatemia e a hipocalcemia desencadeadas pelo hipertireoidismo. Com relação à fosfatase alcalina, conclui-se que o hipertireoidismo reduz o efeito do hipogonadismo sobre a atividade dessa enzima.

Hipogonadismo e função tireoidiana em ratas hipertireóideas e eutireóideas

The effects of hypogonadism on thyroid function of hyper and euthyroid rats were measured based on plasmatic profile of thyroid hormones, ovarian steroids, TSH and thyroid histomorphometry. A group of five-month-old ovariectomized Wistar rats were maintained at hyper or euthyroid state for 30, 60 and 90 days. A group of non castrated was used as control. The hyperthyroidism was induced by gastric infusion of L-tiroxin 50µg daily. At the end of each period nine rats of each group were sacrificed, the blood plasma collected and the thyroid inspected, measured and processed for histomorphometric analyses. In blood plasma the concentrations of estradiol, progesterone, total and free tiroxin, total and free T3 and TSH were determined. The hypogonadism did not alter the values of free T3 and TSH but was able to rise free tiroxin in both hyper and euthyroid states. Total tiroxin levels were affected by castration, but only in the hyperthyroid state. Folicular epithelium height presented variations along the experiment in euthyroid individuals although these did not influence thyroid weight. No correlations between estrogen and any other variables were observed, but the progesterone levels were conversely proportional to the total and free tiroxin levels. It was concluded that hypogonadism alter the histomorphometric patterns of thyroid gland in euthyroid individuals, rise the plasmatic levels of free tiroxin regardless the functional state of thyroid gland and powered the total tyroxin rise in hyperthyroidism, probably due to the influence of hypoprogesteronism but not to the hypoestrogenism.

A influência do hipogonadismo sobre a função tireoidiana de ratas hipertireóideas e eutireóideas foi medida com base no perfil sérico dos hormônios tireoidianos, dos esteróides ovarianos e do TSH e na histomorfometria da tireóide. Ratas Wistar, com cinco meses de idade, castradas, foram mantidas em estado eutireóideo ou hipertireóideo por períodos de 30, 60 e 90 dias. Um grupo não castrado foi mantido nas mesmas condições e serviu como controle. O hipertireoidismo foi induzido mediante a administração diária 50µg de L-tiroxina, por sonda gástrica. Ao final de cada período, nove ratas por grupo tiveram suas tireóides inspecionadas, pesadas e processadas para avaliação histomorfométrica e o plasma sangüíneo colhido para dosagem de estradiol, progesterona, T4 total, T4 livre, T3 total e TSH. O hipogonadismo não alterou os valores de T3 total e de TSH, mas aumentou significativamente as concentrações de T4 livre, independente do estado hipertireóideo ou eutireóideo. As concentrações de T4 total sofreram influência da castração apenas no grupo hipertireóideo. O peso das tireóides não sofreu influência do hipogonadismo, mas a altura do epitélio folicular nos animais eutireóideos variou ao longo do experimento, apresentando-se maior aos 30 e 90 dias e menor aos 60 dias. Não se observou correlação entre os níveis de estrógeno e as variáveis estudadas, mas os níveis de progesterona foram inversamente proporcionais à elevação dos níveis de T4 total e T4 livre. Concluiu-se que o hipogonadismo altera a histomorfometria da tireoide em indivíduos eutireóideos, aumenta os valores plasmáticos de T4 livre independentemente do estado funcional da tireóide e potencializa a elevação de T4 total no hipertireoidismo, provavelmente sob influência do hipoprogesteronismo e não do hipoestrogenismo.

Influência do hipogonadismo na histomorfometria e função tireoidiana de ratas hipotireóideas

The morphology and function of the thyroids of female adult Wistar rats were investigated. The animals were either castrated or intact and kept in a hypothyroid condition by a treatment with propylthiouracil for 120 days. Castrated and intact euthyroid rats were used as controls. The thyroids were collected at the end of the experiment, weighted, histologically processed, and morphometrically evaluated. Proportions of each glandular component, namely, follicular epithelium, colloid, and stroma, were determined. Serum concentrations of total T3, free T4, and TSH were assessed at the end of the experimental period. The weight and the morphometric parameters were not influenced by castration, whereas an increase in the epithelial component associated with a decreased amount of colloid were observed only in hypothyroid animals. Under an euthyroid state, the deficiency of sexual hormones induced an increase in the levels of free T4 and total T3. In hypothyroid animals, withdrawal of sexual hormones caused an exacerbation of the decrease in total T3, but not in free T4. TSH levels were not affected by the thyroid or the functional condition of gonads. In conclusion, hypogonadism did not influence the glandular hyperplasia and decrease in plasmatic levels of free thyroxin induced by propylthiouracil, but markedly changed the profile of total T3 according to the functional condition of the thyroid, in the absence of changes in the plasmatic levels of TSH.

Foram investigadas a morfologia e a função tireoidiana de ratas Wistar, adultas, castradas e não castradas e mantidas em estado hipotireóideo pela administração diária de propiltiouracil por 120 dias. Ratas eutireóideas castradas e não castradas serviram de controle. As tireóides, colhidas ao final do experimento, foram pesadas, processadas histologicamente e submetidas à análise morfométrica, pela qual foi determinada a proporção dos componentes glandulares (epitélio folicular, colóide e estroma). No plasma sangüíneo, colhido também ao final do período experimental, foram determinadas as concentrações de T3 total, T4 livre e TSH. O peso e a histomorfometria da tireóide não sofreu influência da castração e o aumento do componente epitelial e decréscimo da quantidade de colóide só foram detectados no hipotireoidismo. No estado eutireóideo a deficiência dos esteróides sexuais levou ao aumento dos valores de T4 livre e T3 total e no hipotireoidismo, exacerbou a queda de T3 total, mas não a de T4 livre. Os valores de TSH não se alteraram em nenhum dos estados funcionais da glândula ou das gônadas. Conclui-se que o hipogonadismo não modifica a hiperplasia glandular e a queda dos níveis plasmáticos de tiroxina livre induzidos pelo propiltiouracil, mas altera profundamente o comportamento da triiodotironina total de acordo com o estado funcional da tireóide, tudo sem alterar os valores plasmáticos de TSH.