Efect of neonatally administered MSG on the GH and IGF-1 axis

AP GARCÍA; V. SALAZAR; C. ARIZNAVARRETA; M HERMANUSSEN ; J. A. F. TRESGUERRES

Sevilla

Congreso; XXXIII Congres of the Spanish Society of Physiological Sciences; 2005

Spanish Society of Physiological Sciences

ABSTRACT It is well known that parenteral neonatal monosodium glutamate (MSG) administration has toxic effects on arcuate nucleus neurons, leading to significant reductions in plasma of GH and IGF-1 levels. The present study was undertaken to investigate whether oral MSG administration was able to produce the same effect. Thirty pregnant Wistar rats were separated in three groups, receiving diets containing 0, 2.5, or 5.0 g/day MSG from day 14th of pregnancy onwards. A fourth group of animals received standard rat chow, but their offspring was neonatally injected with MSG. After weaning, MSG feeding was continued in the first three groups at the same concentrations in the offspring until day 90 of life. Half of the pups were sacrificed at day 30 of life and the rest at day 90. Blood and brain samples were collected for GH and IGF-1 determinations and volume analysis of the arcuate nucleus. As expected, plasma GH and IGF-1 levels were significantly reduced in animals neonatally injected with MSG, both on day 30 and on day 90 of life (p