Participação da via alfa-2 adrenérgica no controle da secreção do hormônio do crescimento no período prépúbere em novilhas da raça Nelore

This study investigated GH secretion after clonidine (alpha-2 adrenergic agonist) treatment in pre-pubertal Nelore heifers. Clonidine (10 mg/kg, IV, 15 min samples for 4 h) was administrated in the same Nelore heifers at eight (n = 4), 12 (n = 5) and 15 (n = 4) months of age. The GH concentration wa...

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Detalles Bibliográficos
Autores: de Oliveira Santana Batista, Emiliana [UNESP], Cardoso, Daniel, de Paula Nogueira, Guilherme [UNESP]
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2011
País:Brasil
Institución:Universidade Estadual Paulista (UNESP)
Repositorio:Repositório Institucional da UNESP
Idioma:inglés
portugués
OAI Identifier:oai:repositorio.unesp.br:11449/73011
Acceso en línea:http://www.revistas.usp.br/bjvras/article/view/34397
http://hdl.handle.net/11449/73011
Access Level:acceso abierto
Palabra clave:Clonidine
GH
Nelore
Prepubertal
Descripción
Sumario:This study investigated GH secretion after clonidine (alpha-2 adrenergic agonist) treatment in pre-pubertal Nelore heifers. Clonidine (10 mg/kg, IV, 15 min samples for 4 h) was administrated in the same Nelore heifers at eight (n = 4), 12 (n = 5) and 15 (n = 4) months of age. The GH concentration was measured by radioimmunoassay (sensivity = 0.25 ng/mL, CV = 16%). At eight months, clonidine increased GH average concentration, total area of peaks, the total area of GH secretion and increased peak amplitude and reduced time to onset of peak (P < 0.05). At 15 months, the administration of clonidine increased the GH average concentration and at 12 months the increased occurred only in restricted intervals (P < 0.05). Clonidine injection stimulated GH secretion in prepubertal heifers and this effect was more evident in Nelore heifers at eight months compared to 12 and 15 months of age.