Lactate activates the somatotropic axis in rats

Autor(es)

Salgueiro, Rafael Barrera ^[1] ; Peliciari-Garcia, Rodrigo A. ^[1] ; Buonfiglio, Daniella do Carmo ^[1] ; Peroni, Cibele Nunes ^[2] ; Nunes, Maria Tereza ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Biomed Sci 1, Dept Physiol & Biophys, BR-05508900 Sao Paulo - Brazil

^[2] Nucl & Energy Res Inst IPEN, Ctr Biotechnol, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: GROWTH HORMONE & IGF RESEARCH; v. 24, n. 6, p. 268-270, DEC 2014.
• Citações Web of Science: 2

Resumo

Under physical activity a wide variety of cellular metabolic products and hormones are altered in the blood stream, including lactate, a metabolite of pyruvate reduction, and growth hormone (GH). Although a positive correlation between lactate and GH seems to exist during exercise, the role of lactate as a mediator of GH production has never been investigated. Thus, the aim of this study was to investigate whether lactate could activate the somatotropic axis and stimulate GH synthesis/release, contributing to the enhanced somatotropic activity described in exercise conditions. Male adult Wistar rats were acutely treated with sodium lactate 115 or 150 mu mols, i.p.] at the beginning of the active period (Zeitgeber time 13-14), and euthanized by decapitation 30, 60 and 120 min after the injections. Serum GH concentration were determined using ELISA and Gh and Igf-1 mRNA expressions were quantified by qPCR. Serum GH concentration and Gh mRNA expression were increased 30 min after lactate injections for both treatments. However, {[}15 mu mols] of lactate injection kept GH serum concentration chronically high throughout the experimental period. Igf-1 mRNA expression was increased only 60 min after challenge with {[}15 mu mols] of lactate, time point which corresponded to 30 min after the serum GH peak. The present results led us to conclude that lactate mediates activation of the somatotropic axis, therefore emphasizing its possible role on GH synthesis/release, and-further indicating that it could play a part on-the increased GH secretion observed in exercise conditions. (C) 2014 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 11/14961-7 - Efeito da infusão do lactato sobre a atividade do eixo gh-igf-i em ratos
• Beneficiário: Rafael Barrera Salgueiro
• Modalidade de apoio: Bolsas no Brasil - Mestrado