A characteristic pathological feature of Parkinson's disease is presence of -
Pathologic Examination in Parkinson shows :

Gross / Macroscopically: Pallor of the substantia nigra and locus coeruleus
Microscopic Examination :    

1. Loss of catecholaminergic neurons in these regions + gliosis
2. Lewy bodies.

Lewy bodies: are inclusion bodies found within neurons in Parkinson's disease.
Lewy bodies are single or multiple, intra-cytoplasmic, eosinophilic, round and elongated inclusions that often have a dense core surrounded by a pale halo.
Ultrastructurally: These are composed of fine filaments, densely packed in the core but loose at the rim.
Lewy bodies
Babes nodule
Neuro fibrillary tangle
Negri-bodies