Plasticity neuronal regeneration

The recognition that cells such as neurons and muscle or cardiac cells, which were previously considered incapable of proliferating in old age, retain the potential for plasticity and regeneration has opened the way to the study of intrinsic and extrinsic factors that may facilitate tissue repair in neurodegenerative diseases of old age. Likewise, the identification of pluripotent cells, such as stem cells, that are potentially capable of acquiring the structure and function of a variety of specialized cells promises to let us effectively replace lost tissues and functions. 

Cell adhesion molecules (CAMs) play critical roles in all facets of nervous system development and maintenance. Important phenomena in which CAMs are involved include initial formation of the neural tube and the neural crest, migration of all neurons and glial cells, axonal outgrowth and guidance, target selection, synaptic stabilization and plasticity, myelination and nerve regeneration after injury (see Chs 4,24,28-30 and 53). Adhesion molecules interact with each other and with nonadhesive cell-surface and/or cytoplasmic molecules, and, in the two... 

Damage to the adnlt brain or spinal cord commonly prodnces persistent dysfnnction withont recovery. To replace lost nenron stem cells, trophic factors, and transplantation of nenral-competent cells might be relevant. Treatment of dysfnnction based on the disconnection of snrviving nenrons reqnires the axonal regeneration from remaining nenrons and a degree of plasticity in neuronal connectivity. 

Hill, C.E. and Vidovic, M. (1992) Projections of sympathetic neurons to targets during development in vivo. In l.A. Hendry and C.E. Hill (Eds.), Development, Regeneration and Plasticity of the Autonomic Nervous System, Ch. 4, Harwood Academic Publishers, London, pp. 179-230. 

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