Dopamine Release Neuroenergetics in Mouse Striatal Slices

Area of Science:

• Neuroscience
• Cellular Metabolism
• Neurodegenerative Diseases

Background:

• Parkinson's disease (PD) involves degeneration of dopamine (DA) neurons projecting to the dorsal striatum (dSTR).
• DA neurons in the ventral striatum, including the nucleus accumbens (NAcc) shell, are relatively spared in PD.
• Understanding energy metabolism differences in striatal DA terminals may explain selective vulnerability.

Purpose of the Study:

• To investigate the distinct contributions of glycolysis and oxidative phosphorylation (OxPhos) to dopamine release in the dSTR and NAcc shell.
• To elucidate the metabolic basis for the differential vulnerability of striatal dopamine terminals in Parkinson's disease.

Main Methods:

• Fast-scan cyclic voltammetry was used to measure evoked DA release in mouse striatal brain slices.
• Metabolic inhibitors were applied to selectively block glycolysis or OxPhos.
• Two-photon imaging assessed DA terminal oxidation levels.

Main Results:

• Blocking OxPhos significantly reduced DA release in the dSTR more than in the NAcc shell.
• Blocking glycolysis more severely impaired DA release in the NAcc shell compared to the dSTR.
• The NAcc shell showed a marked decrease in DA release when relying solely on OxPhos, unlike the dSTR.

Conclusions:

• The dorsal striatum primarily utilizes OxPhos for maintaining evoked DA release.
• The nucleus accumbens shell preferentially depends on glycolysis for DA release.
• These distinct metabolic profiles contribute to the selective degeneration of dSTR DA terminals in Parkinson's disease.