Hippocampal Stimulation of Cholinergic Expression in Primary Cultures of Basal Forebrain Neurons

Abstract

A major goal of development neurobiology is to define the cellular and molecular mechanisms which regulate the survival, growth and synaptogenesis of central nervous system neurons. A role for specific neurotrophic factors in CNS development has been postulated based on described processes occurring in the peripheral nervous system such as naturally occurring neuronal death (Cowan et al., 1984). Such a process might serve to match the size of the afferent neuronal population with that of the target area of innervation. A factor determining neuronal death might be neuronal competition for a limited quantity of trophic factors present in the target region. The identification, characterization and our present understanding of the physiology of the nerve growth factor (NGF) emphasizes the importance of target-drived molecules on the survival, growth and differentiation of an afferent neuronal population (Thoenen and Barde, 1980; Yanker and Shooter, 1982). In mature neurons the maintenance of a critical number of terminal boutons may also require trophic support, albeit at a much lower level than is needed during development. Neurodegenerative diseases, such as senile and presenile dementias, may be caused in part by abnormalities in the supply of neurotrophic factors specific for certain neurons (Appel, 1981).