The dopamine transporter (DAT, encoded by SLC6A3) is a critical regulator of dopaminergic neurotransmission. DAT mediates the high-affinity reuptake of dopamine from the synaptic cleft back into presynaptic neurons, playing a key role in terminating dopaminergic signaling. In Parkinson's disease, DAT function is altered, and targeting this transporter offers a therapeutic approach to modulate dopamine homeostasis[1].
DAT modulators can function through several mechanisms:
This approach differs from direct dopamine receptor agonists, offering an alternative mechanism for dopaminergic stimulation.
| Company | Program | Mechanism | Development Stage |
|---|---|---|---|
| Neurocrine Biosciences | Multiple dopamine programs | DAT modulators | Research |
| Bristol Myers Squibb | DAT-directed compounds | DAT antagonist | Preclinical |
| Merck | DAT research programs | DAT modulation | Discovery |
Several companies use DAT imaging as a biomarker for Parkinson's disease diagnosis and progression:
| Company | Approach | Application |
|---|---|---|
| Life Molecular Imaging | DaTscan (Ioflupane) | DAT SPECT imaging |
| GE Healthcare | DAT imaging agents | PD diagnosis |
| Piramal Imaging | DAT imaging | Dopaminergic neuron loss |
The DAT modulator space for Parkinson's disease remains largely preclinical, with several challenges:
The dopamine transporter is a member of the neurotransmitter sodium symporter (NSS) family, requiring sodium and chloride ions for transport. DAT is primarily expressed in:
In PD, DAT binding is reduced due to loss of nigral dopamine neurons. DAT imaging (DaTscan) is used clinically to confirm dopaminergic deficit. However, therapeutic targeting of DAT remains an underexplored area compared to receptor-based approaches.