RESUMO
Eight-week-old calves were either castrated by partial scrotal resection (SR) without removing the testes (n = 10), Burdizzo (BZ) clamp (n = 10), orchidectomy (OR; n = 10), or were left gonad intact as controls (CO; n = 10). Concentrations of anti-Muellerian hormone (AMH), inhibin A, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) in plasma were determined from 16 to 48 weeks of age. At 18 months, testes of SR, BZ, and CO bulls were obtained and the immunolocalization of LH and FSH receptors and AMH analyzed. Concentration of AMH in plasma of CO and SR bulls decreased with increasing age (P < 0.001). A similar AMH profile in CO and SR indicates that SR did not induce a true cryptorchid state. In groups OR and BZ, AMH was undetectable. Plasma inhibin concentration was higher in groups CO and SR than BZ and OR (P < 0.001). Plasma LH and FSH concentrations decreased over time (P < 0.001) and were higher in groups BZ and OR than SR and CO (P < 0.001). In the testes, immunolabeling for AMH existed in Sertoli cells of CO and SR but not BZ bulls. FSH receptors were localized in Sertoli cells, Leydig cells, spermatocytes, and the epididymis of CO and SR animals, whereas LH receptors were restricted to Leydig cells. In BZ animals, FSH and LH receptors and AMH were absent, indicating complete testicular degeneration. In conclusion, AMH is a more reliable marker for the presence of testicular tissue in bulls than inhibin. Scrotal resection did not induce a true inguinal cryptorchid state but affected testicular responsiveness to gonadotropic stimulation.
Assuntos
Hormônio Antimülleriano/sangue , Bovinos/fisiologia , Gonadotropinas/sangue , Inibinas/sangue , Orquiectomia/veterinária , Receptores da Gonadotropina/sangue , Animais , Hormônio Antimülleriano/metabolismo , Bovinos/sangue , Bovinos/cirurgia , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/genética , Hormônio Foliculoestimulante/metabolismo , Regulação da Expressão Gênica/fisiologia , Gonadotropinas/metabolismo , Inibinas/genética , Inibinas/metabolismo , Hormônio Luteinizante/sangue , Hormônio Luteinizante/genética , Hormônio Luteinizante/metabolismo , Masculino , Orquiectomia/métodos , Receptores do FSH/sangue , Receptores do FSH/genética , Receptores do FSH/metabolismo , Receptores da Gonadotropina/genética , Receptores da Gonadotropina/metabolismo , Receptores do LH/sangue , Receptores do LH/genética , Receptores do LH/metabolismo , Escroto/cirurgiaRESUMO
Introdução: A puberdade precoce central ocorre principalmente devido a ativação precoce do eixo hipotalâmico-hipofisário-gonadal e conseqüentemente ao aumento do hormônios gonadotróficos. A prematura ativação desse eixo não envolve apenas mudanças físicas precoces da puberdade, mas também aceleração do crescimento linear e aceleração da maturação óssea, que leva a fusão das epífises ósseas de maneira prematura e à diminuição da altura final. Objetivo: Identificar a altura final de pacientes que apresentaram Puberdade Precoce Central atendidos no Serviço de Endocrinologia Pediátrica do Hospital Infantil Joana de Gusmão. Métodos: Foram avaliados os registros de pacientes que haviam atingido a AF no período de 1997-2007. As variáveis analisadas foram: sexo, idade cronológica, idade óssea, idade ao diagnóstico, idade ao atingir a altura final, tempo de tratamento até altura final, tempo de acompanhamento até a altura final, tratamento utilizado, altura no início e término do tratamento, altura predita pelo método de Bayley Pinneau, altura-alvo e altura final ( transformada em escore z). Resultados: Foram incluídos 56 pacientes, 96,4 % do sexo feminino e 90,75 % dos pacientes apresentavam PPC idiopática. Os pacientes masculinos foram tratados com análogo do hormônio liberador de gonadotrofinas por 2,7 anos em média, enquanto que as pacientes femininas foram tratadas durante 3,1 anos. A altura final foi alcançada aos 15,1 anos nos meninos e 14,2 anos nas meninas.Conclusões: A média de altura final foi 171,25 cm no sexo masculino e 160,77 cm no sexo feminino. O escore-z de AF foi de -0,55 desvios padrão da média nos meninos e 0,04 desvios padrão da média nas meninas. A diferença entre altura final e altura alvo foi de -5,25 cm nos meninos e 2,4 cm nas meninas.
Background: Central precocious puberty is mainly due to the precocious activation of hypothalamic-pituitary-gonadal axis leading to an increase of gonadotropic hormones. The premature activation of this axis it involves not only early physical changes of puberty, but also linear growth acceleration and acceleration of bone maturation, which leads to early epiphyseal fusion and short adult height. Objective: To identify final height in central precocious puberty patients treated at Pediatric Endocrinology Service of Hospital Infantil Joana de Gusmão. Methods: The study evaluated the registration of patients that had reached the final height between 1997-2007. Data included sex, chronological age, bone age, age at diagnosis, age at final height, duration of treatment, duration of accompaniment from the start of treatment to final height, treatment used, height at the start and at the end of treatment, predicted height by Bayley Pinneau method, target height and final height (these are transformed in z-score). Results: Fifty six patients were involved. 96,4 % were female sex and 90,75 % had idiopathic central precocious puberty. The males were treated with Gonadotropin Releasing Hormone Analogue by 2,7 years and females were treated by 3,1 years. Final height was reached at 15,1 years in boys and 14,2 years in girls. Conclusions: Final height average was 171,25 cm in males and 160,77 cm in females. The z-score of final height was -0,55 standard deviation of average in boys and 0,04 standard deviation of average in girls. The difference between final height and target height were -5,25 cm in boys and 2,4 cm in girls.
