1 Review 2 3 Diverse midbrain dopaminergic neuron subtypes and implications for complex 4 clinical symptoms of Parkinson's disease 5 6 Kathleen Carmichael1,2, Breanna Sullivan1, Elena Lopez1, Lixin Sun1, Huaibin 7 Cai1, * 8 9 1Transgenic Section, Laboratory of Neurogenetics, National Institute on Ageing, 10 National Institutes of Health, Bethesda, MD 20892, USA. 11 2The Graduate Partnership Program of NIH and Brown University, National Institutes 12 of Health, Bethesda, MD 20892, USA. 13 14 Correspondence to: Dr. Huaibin Cai, Transgenics Section, Laboratory of 15 Neurogenetics, National Institute on Ageing, National Institutes of Health, Building 35, 16 Room 1A112, MSC 3707, 35 Convent Drive, Bethesda, MD 20892–3707, USA. E-mail: 17
[email protected] 18 19 How to cite this article: Carmichael K, Sullivan B, Lopez E, Sun L, Cai H. Diverse 20 midbrain dopaminergic neuron subtypes and implications for complex clinical 21 symptoms of Parkinson's disease. Ageing Neur Dis 2021;1:[Accept]. 22 http://dx.doi.org/10.20517/and.2021.07 23 24 Received: 16 Jun 2021 Revised: 12 Jul 2021 Accepted: 14 Jul 2021 First online: 25 15 Jul 2021 26 27 28 Abstract 29 Parkinson's disease (PD), the most common degenerative movement disorder, is 30 clinically manifested with various motor and non-motor symptoms. Degeneration of 31 midbrain substantia nigra pas compacta (SNc) dopaminergic neurons (DANs) is 32 generally attributed to the motor syndrome. The underlying neuronal mechanisms of 33 non-motor syndrome is largely unexplored. Besides SNc, midbrain ventral tegmental 34 area (VTA) DANs also produce and release dopamine and modulate movement, reward, 35 motivation, and memory.