Neonatal monosodium glutamate administration increases aminooxyacetic acid (AOA) susceptibility effects in adult mice.

Neonatal administration of monosodium glutamate (MSG) to mice causes neurotoxicity of the CNS resulting in endocrine, metabolic and behavioral abnormalities. Aminooxyacetic acid (AOAA) is a potent inhibitor of GABA-transaminase and increases GABA levels in the brain. In this work, we studied the effect of neonatal treatment of CFW mice with MSG (2 mg/g sc on the 2nd and 4th days after birth followed by 4 mg/g on days 6, 8 and 10) on AOAA- (100 to 250 mg/kg ip) induced hypothermia, hypnosis and lethality after six months of treatment. The control group was vehicle-treated only. MSG treatment significantly increased susceptibility to the hypothermic, hypnotic and lethal effect of AOAA acutely administered. The increased susceptibility to the depressor effects of AOAA may occur as a consequence of changes in neural excitability, up regulation of GABA-receptors or might be related to pharmacokinetic modifications induced by neonatal treatment with MSG.