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1.
Endocrinol Metab Clin North Am ; 46(2): 283-303, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28476224

RESUMO

Congenital isolated hypogonadotropic hypogonadism (IHH) is a clinically and genetically heterogenous disorder characterized by abnormal synthesis, secretion, or action of gonadotropin-releasing hormone, a key hypothalamic decapeptide that orchestrates the reproductive axis. Several modes of inheritance have been identified. A growing list of causative genes has been implicated in the molecular pathogenesis of syndromic and nonsyndromic IHH, largely contributing for better understanding the complex neuroendocrine control of reproduction. This article summarizes the great advances of molecular genetics of IHH and pointed up the heterogeneity and complexity of the genetic basis of this condition.


Assuntos
Hormônio Liberador de Gonadotropina/deficiência , Hipogonadismo/congênito , Hipogonadismo/genética , Humanos , Hipotálamo/fisiopatologia
2.
Acta sci. vet. (Online) ; 44: 01-07, 2016. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-722717

RESUMO

Background: Milk production of cows is closely correlated with its reproductive efficiency. One of the several factors influencing the dairy efficiency is the decline in fertility of the cows/heifers. Use of hormonal protocol are often used to improve the fertility of the recipients. Several programs are available to inseminate dairy cows, with variation in the use of different types of hormones, time of use and range of duration period, as well as the time of AI. The objective of this study was to evaluate the efficiency of follicular wave emergence induction of estradiol benzoate in comparison to GnRH in a Heatsynch protocol and its influence on reproductive parameters. Materials, Methods & Results: In this study were used primiparous and multiparous Holstein cows (n = 325). Animals were divided randomly into two different treatments according with the hormone used to induce follicular wave emergence (D0). The GnRH group (n = 167), was given 25 mg, while in the EB group (n = 158) was used 2 mg. At same day, were inserted, a controlled internal drug-releasing containing 1.9 g of progesterone CIDR®. On day 7, CIDR was removed and cows were given 25 mg luteinizing hormone followed by an injection of 1 mg Inducer Ovulation at day 8. Cows were then observed for signs of estrus for at least two hours (twice daily at 7 am and 6 pm) for three days following CIDR® removal. Cows [...](AU)


Assuntos
Animais , Feminino , Bovinos , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/análise , Hormônio Liberador de Gonadotropina/deficiência , Leite , Benzoatos/análise , Estradiol/análise , Folículo Ovariano , Estro , Substâncias para o Controle da Reprodução , Taxa de Gravidez
3.
Acta sci. vet. (Impr.) ; 44: 01-07, 2016. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1457448

RESUMO

Background: Milk production of cows is closely correlated with its reproductive efficiency. One of the several factors influencing the dairy efficiency is the decline in fertility of the cows/heifers. Use of hormonal protocol are often used to improve the fertility of the recipients. Several programs are available to inseminate dairy cows, with variation in the use of different types of hormones, time of use and range of duration period, as well as the time of AI. The objective of this study was to evaluate the efficiency of follicular wave emergence induction of estradiol benzoate in comparison to GnRH in a Heatsynch protocol and its influence on reproductive parameters. Materials, Methods & Results: In this study were used primiparous and multiparous Holstein cows (n = 325). Animals were divided randomly into two different treatments according with the hormone used to induce follicular wave emergence (D0). The GnRH group (n = 167), was given 25 mg, while in the EB group (n = 158) was used 2 mg. At same day, were inserted, a controlled internal drug-releasing containing 1.9 g of progesterone CIDR®. On day 7, CIDR was removed and cows were given 25 mg luteinizing hormone followed by an injection of 1 mg Inducer Ovulation at day 8. Cows were then observed for signs of estrus for at least two hours (twice daily at 7 am and 6 pm) for three days following CIDR® removal. Cows [...]


Assuntos
Feminino , Animais , Bovinos , Benzoatos/análise , Estradiol/análise , Estro , Folículo Ovariano , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/análise , Hormônio Liberador de Gonadotropina/deficiência , Leite , Substâncias para o Controle da Reprodução , Taxa de Gravidez
4.
Neuroendocrinology ; 98(3): 212-23, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24080944

RESUMO

BACKGROUND/AIMS: Adult mice lacking functional GABAB receptors (GABAB1KO) show altered Gnrh1 and Gad1 expressions in the preoptic area-anterior hypothalamus (POA-AH) and females display disruption of cyclicity and fertility. Here we addressed whether sexual differentiation of the brain and the proper wiring of the GnRH and kisspeptin systems were already disturbed in postnatal day 4 (PND4) GABAB1KO mice. METHODS: PND4 wild-type (WT) and GABAB1KO mice of both sexes were sacrificed; tissues were collected to determine mRNA expression (qPCR), amino acids (HPLC), and hormones (RIA and/or IHC). RESULTS: GnRH neuron number (IHC) did not differ among groups in olfactory bulbs or OVLT-POA. Gnrh1 mRNA (qPCR) in POA-AH was similar among groups. Gnrh1 mRNA in medial basal hypothalamus (MBH) was similar in WTs but was increased in GABAB1KO females compared to GABAB1KO males. Hypothalamic GnRH (RIA) was sexually different in WTs (males > females), but this sex difference was lost in GABAB1KOs; the same pattern was observed when analyzing only the MBH, but not in the POA-AH. Arcuate nucleus Kiss1 mRNA (micropunch-qPCR) was higher in WT females than in WT males and GABAB1KO females. Gad1 mRNA in MBH was increased in GABAB1KO females compared to GABAB1KO males. Serum LH and gonadal estradiol content were also increased in GABAB1KOs. CONCLUSION: We demonstrate that GABABRs participate in the sexual differentiation of the ARC/MBH, because sex differences in several reproductive genes, such as Gad1, Kiss1 and Gnrh1, are critically disturbed in GABAB1KO mice at PND4, probably altering the organization and development of neural circuits governing the reproductive axis.


Assuntos
Glutamato Descarboxilase/deficiência , Hormônio Liberador de Gonadotropina/deficiência , Hipotálamo Médio/metabolismo , Kisspeptinas/deficiência , Precursores de Proteínas/deficiência , Receptores de GABA-B/deficiência , Diferenciação Sexual/genética , Animais , Animais Recém-Nascidos , Núcleo Arqueado do Hipotálamo/crescimento & desenvolvimento , Núcleo Arqueado do Hipotálamo/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Glutamato Descarboxilase/genética , Hormônio Liberador de Gonadotropina/genética , Hipotálamo Médio/crescimento & desenvolvimento , Kisspeptinas/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Precursores de Proteínas/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores de GABA-B/genética
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