Low doses of L-monosodium glutamate promote neuronal growth and differentiation in vitro.

Monosodium glutamate given at a concentration of 5 X 10(-6) M to whole-brain dissociated cultures of 18-day-old rats promotes neuronal growth. Neurons are larger due to an increased size of both cytoplasm and nucleus. Rough endoplasmic reticulum is more developed and mitochondria are more abundant. Synaptic vesicles are significantly increased in number with respect to control cultures. Synapses are more abundant and show a more differentiated morphology. These findings are interpreted as evidence for accelerated development secondary to the stimulatory effects of glutamate.