The Mammalian Peripheral Nervous System in Old Age

Stathmin-Deficient Mice Develop an Age-Dependent Axonopathy of the Central and Peripheral Nervous Systems

“…54,55 They also did not resemble findings from previously characterized age-related mouse models of neurodegeneration, such as age-related atrophic changes in motor axons of mice deficient in the mid-sized NF subunit, 56 or acquired changes seen in toxic or metabolic neuropathies.…”

Age-related Atrophy of Motor Axons in Mice Deficient in the Mid-sized Neurofilament Subunit

“…As noted above, some perikaryal and axonal atrophy is considered a normal aspect of aging (Peters and Vaughn, 1981;Spencer and Ochoa, 1981). Although the molecular alterations underlying these changes remain incompletely described, an age related decrease in NF mRNA levels has been observed in rodents during normal aging (Parhad et al, 1995;Kuchel et al, 1997).…”

“…Some degree of perikaryal and axonal atrophy is considered a normal aspect of aging (Peters and Vaughn, 1981;Spencer and Ochoa, 1981) and normal lumbar ventral roots do undergo an age-related reduction in axonal caliber (see Fig. 6).…”

Changes with Age in the Number and Size of Myelinated Axons in the Rat L₄ Dorsal Spinal Root

“…This size is attributed to the large diameter of radicular axons and the enormous length of the lumbar internodes. The demyelination of spinal roots in the aging rat is more common in large diameter fibres than in those of smaller calibre -in lumbosacral roots rather than in other spinal roots and in ventral rather than dorsal roots [Spencer and Ochoa, 1981],…”

“…However, the present values of sensory cyton size have only a preliminary character, since the approach used until now was insuf ficient due to both the small number of examined cells and to the lack of stereologic technique to correct errors produced by examining several populations of multi dimensional cells in two-dimensional sec tions. Alterations of cell size and number with age in the rat dorsal root ganglia still await systematic studies [Spencer and Ochoa, 1981], There is sufficient evidence of lipofuscin accumulation in the rat dorsal root perikarya, commencing as early as the age of 3 months and progressively augment ing to form prominent aggregates with advanced age [van den Bosch de Aguilar and Vanneste, 1981]. Since lipofuscin can accumulate at the expense of cytoplasmic ribonucleic acid and of the 'nucleus-ribo some system' [Spoerri et al, 1981], it is con ceivable that the relative capability of pro tein synthesis in affected neurons could gradually decrease even during the period of continuous neuronal growth.…”