Alterations in Calcium Homeostatic Capacity: A Locus for Constructive and Destructive Neuronal Remodeling

Abstract

L-Glutamate is one of the major excitatory neurotransmitters in the central nervous system. We have been investigating neurons from the hippocampus, where glutamate is thought to be the transmitter of the Schaffer collateral-commissural pathway and the hippocampal perforant path (Crawford and Connor 1973; Nadler et al. 1978). Glutamate appears to have several roles in the nervous system. There is a well-documented role for glutamate in normal synaptic transmission. In addition, the overactivity of glutamate systems has been implicated in a variety of neurological diseases (for review, see Choi 1988) such as Alzheimer’s (Geddes et al. 1986; Hyman et al. 1987; Maragos et al. 1987), epilepsy (Schwarcz et al. 1984), Huntington’s disease (Coyle and Schwarcz 1976), and stroke (Rothman 1984; Simon et al. 1984). Along with these fonctions, we have demonstrated another role for glutamate: glutamate and related excitatory amino acids may play specific roles in both the generation and degeneration of hippocampal neurons (Mattson et al. 1988a,b, 1989; Mattson and Kater 1989).

Program of Neuronal Growth and Development, Department of Anatomy, Colorado State University, Fort Collins, Colorado 80512, USA