ABSTRACT
Alpha-synuclein (alpha-syn) is a presynaptic protein that is richly expressed in the central and peripheral nervous systems of mammals, and it is related to the pathogenesis of Parkinson's disease and other neurodegenerative disorders. In the present study, we compared the distribution of the immunoreactivity of alpha-syn and its related gliosis in the spinal cord of young adult (2-3 years) and aged (10-12 years) beagle dogs. We discovered that alpha-syn immunoreactivity was present in many neurons in the thoracic level of the aged spinal cord, however, its protein level was not distinct inform that of the adult spinal cord. In addition, ionized calcium-binding adapter molecule-1 (a marker for microglia) immunoreactivity, and not glial fibrillary acidic protein (a marker for astrocytes) immunoreactivity, was somewhat increased in the aged group compared to the adult group. These results indicate that alpha-syn immunoreactivity was not dramatically changed in the dog spinal cord during aging.