| AD | Alzheimer’s Disease |
| BBB | Blood–Brain Barrier |
| CNS | Central Nervous System |
| CSF | Cerebrospinal Fluid |
| DA | Dopaminergic |
| DBH | Dopamine-β-hydroxylase |
| DOPEGAL | 3,4-Dihydroxyphenylglycolaldehyde |
| LBD | Lewy Body Dementia |
| LC | Locus Coeruleus |
| MCI | Mild Cognitive Impairment |
| MSA | Multiple System Atrophy |
| NA | Noradrenaline |
| NAT | Noradrenaline Transporter |
| NDDs | Neurodegenerative Diseases |
| NFTs | Neurofibrillary Tangles |
| NM | Neuromelanin |
| PD | Parkinson’s Disease |
| ROS | Reactive Oxygen Species |
| SNpc | Substantia Nigra pars compacta |
| TH | Tyrosine Hydroxylase |