Aging delays the regeneration process following sciatic nerve injury in rats.
The present study investigated the effect of aging on muscle reinnervation in rats following a crush nerve injury. Using confocal laser scanning microscopy, we examined the spatial correlation of terminal Schwann cells (TSCs) or axon terminals with acetylcholine receptor (AChR) sites at neuromuscular junctions (NMJs). Compared to young rats (4 months of age), aged rats (24 months of age) demonstrated damaged TSC extensions and delayed regeneration. Post-injury endplate abnormalities in aged rats correlated with the degree of TSC degeneration. In the late stages of reinnervation, pathologic changes were seen in old rats, including multiple innervations, terminal sprouting, and poorly formed collateral innervation in NMJs. Our results suggest that the impaired TSC-axon interaction in aged rats delays the reinnervation process.
Wang
Yong-Jun
YJ
Institute of Spine, Shanghai University of Traditional Chinese Medicine, Shanghai, China. yjwang88@hotmail.com
Zhou
Chong-Jian
CJ
Shi
Qi
Q
Smith
Nathan
N
Li
Tian-Fang
TF
D000375:Aging / Q000502:physiology; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D020439:Growth Cones / Q000378:metabolism / Q000473:pathology; D008297:Male; D018613:Microscopy, Confocal; D009046:Motor Neurons / Q000378:metabolism / Q000473:pathology; D009416:Nerve Regeneration / Q000502:physiology; D009469:Neuromuscular Junction / Q000473:pathology / Q000503:physiopathology*; D009473:Neuronal Plasticity / Q000502:physiology; D017729:Presynaptic Terminals / Q000378:metabolism / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D011950:Receptors, Cholinergic / Q000378:metabolism; D009418:S100 Proteins / Q000378:metabolism; D012583:Schwann Cells / Q000378:metabolism / Q000473:pathology; D012584:Sciatic Nerve / Q000473:pathology / Q000503:physiopathology*; D020426:Sciatic Neuropathy / Q000473:pathology / Q000503:physiopathology*; D013570:Synaptic Membranes / Q000378:metabolism / Q000473:pathology; D013997:Time Factors; D043222:Ubiquitin Thiolesterase / Q000378:metabolism
D015415:Biomarkers; D011950:Receptors, Cholinergic; D009418:S100 Proteins; C489034:UCHL1 protein, rat; D043222:Ubiquitin Thiolesterase