Axonal degeneration of nigra-striatum dopaminergic neurons induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine in mice.

As one of the main pathological changes of Parkinson's disease (PD), axonal degeneration was thought to be a passive process that is secondary to the apoptosis of dopaminergic neurons and, therefore, it has been overlooked for some time. Recent research, however, has indicated that axonal injury is the first location of damage in dopaminergic neurons in PD, and that the degree of injury in axonal degeneration is higher than in neural death. This study explored the relationship between apoptosis of dopaminergic neurons and their axonal degeneration by observing dopaminergic neuronal injury and axonal degeneration in the substantia nigra-striatum in different animal PD model and control groups. The results show that axonal degeneration plays a crucial role in the pathogenesis of PD and suggest that the process of axonal degeneration occurs independently of apoptosis and may even induce neuronal apoptosis. Thus, preventing axonal degeneration may be a potential new therapeutic strategy for PD.