Brain Damage in Infant Mice following Oral Intake of Glutamate, Aspartate or Cysteine

Abstract

STRIKING degenerative changes in the infant mouse retina after subcutaneous treatment with monosodium glutamate (MSG) were reported by Lucas and Newhouse in 1957¹. Other studies^2–6 established that the process of retinal degeneration induced by MSG treatment is a remarkably acute and irreversible form of neuronal pathology. Recently it was found that a similar process of acute neuronal necrosis occurs in several regions of the infant mouse brain after subcutaneous treatment with MSG, and that animals treated with high doses in infancy tend to manifest obesity and neuroendocrine disturbances as adults^7,8. The arcuate nucleus of the hypothalamus is an area particularly vulnerable to glutamate induced damage in infant animals of several species (mice and rats⁷, rabbits and chicks and the rhesus monkey⁹). In mice, which have been studied more extensively for MSG induced disturbances than other species, the infant animal suffered hypothalamic damage from a relatively low subcutaneous dose (0.5 g/kg of body weight)⁷.