Neurotransmission and the ontogeny of human brain.

The early appearance of neurotransmitters in brain tissue refers to their regulative functions on the neuronal circuits. Many neurotransmitters have direct effects on neuronal outgrowth and differentiation during brain development, which precede their role in synaptic information coding. Both the neurotrophic and neurotoxic properties of excitatory amino acids (EAAs) have focused special interest on glutamatergic neurotransmission during brain development. Therefore, this work intends to review and discuss developmental alterations of the EAA neurotransmitter system in the human brain, their relation to human brain maturation and implications for pathological processes during early human brain development.