Monosodium L-glutamate-induced convulsions--II. Changes in catecholamine concentrations in various brain areas of adult rats.

Norepinephrine (NE) and dopamine (DA) levels in various brain regions were measured in a model of experimentally produced convulsions by monosodium L-glutamate (MSG) administration to adult rats. Stress by injection of all solutions produced a 60% decrease in NE level in forebrain, recovering its basal value at 15 min after injection. A significant reduction of brain NE and DA levels of MSG-injected animals was found in the preconvulsive stage, particularly in the forebrain. No significant variations in catecholamine levels were seen in brain stem and cerebellum as a result of MSG injection. It is suggested that the changes found in endogenous catecholamine concentration in the forebrain may play a physiological role in the mechanisms of production of convulsions in the MSG model.