Neuronal development and apoptosis

There are several distinct mechanisms of neuronal cell death that occurs during development. Nuclear type of cell death involves cell shrinkage and chromatin condensation both typical of apoptosis. Here in this short review we summarize some recent advances concerning the mechanism of nuclear type of neuronal death in vitro. Particular focus is placed on superior cervical ganglion (SCG) cells and neuronal PC12 cells both undergoing apoptosis when they are deprived of NGF or serum/NGF. With regard to presynaptic regulation of neuronal death/survival in SCG both cholinergic and non-cholinergic innervations have a pivotal role. The former may involve the modulation of intracellular free Ca2+ concentration, while the latter may exert its effect through a cAMP-dependent mechanism. Finally, neuronal death/survival mechanism of cerebellar granule cells is discussed in terms of cerebellum development and synaptogenesis. Physiological implications are also described about fyn knockout mouse in which naturally-occurring neuronal death may be greatly impaired.