Effect of neonatal treatment with monosodium glutamate on the secretion of alpha-MSH, beta-endorphin and ACTH in the rat.

Plasma alpha-MSH, beta-endorphin and ACTH were measured at 60 days of age in rats which had been injected during the neonatal period with monosodium glutamate (MSG). Although the arcuate nucleus tuberoinfundibular dopaminergic and cholinergic system was lesioned by the MSG, no change in circulating alpha-MSH, ACTH and corticosterone levels was observed under basal conditions, after ether stress of adrenalectomy. In contrast, a moderate, but significant decrease in plasma beta-endorphin was noticed after MSG treatment.