ABSTRACT
This chapter outlines the major trends in brain development, especially as they relate to excitatory amino acid neurotransmitter systems. It considers the patterns of injury that may result from insults occurring during infancy, it is worthwhile to consider that the postnatal brain is undergoing a transformation in its organization, especially with respect to synaptic connections among neurons. The elaboration of axons and dendrites forming synaptic connections between neurons accounts for a large fraction of brain expansion during the first year of life. Glutamate is the major excitatory neurotransmitter in the brain while gamma-aminobutyric acid is the major inhibitory transmitter. The complexity and selectivity of the actions of these relatively nonspecific amino acid neurotransmitters are imparted by a variety of specific receptors. A major role of excitatory amino acid receptors appears to be to manage the dangerous trophic molecule, calcium. The N-methyl-D-aspartate receptor channel complex is one of the more important channels in physiologic and pathophysiologic processes in the developing brain.
