What systems of the body are affected by parkinson's disease?

Disease of misfolded: Proteins, affecting numerous neurotransmitters, especially a Dopamine deficit. Main brain systems include basal ganglia (especially substantial nigra), but also dorsal vagal nucleus, locus ceruleous, and pallidum. But we are now finding areas of pathology in the gut (meissner's plexus), so this may be more systemic than we used to think.