Regulation of parkinsonian motor behaviours by optogenetic control of basal ganglia circuitry
Alexxai V. Kravitz, Benjamin S. Freeze, Philip R. L. Parker, Kenneth Kay, Myo T. Thwin, Karl Deisseroth& Anatol C. Kreitzer
Nature (2010)
doi:10.1038/nature09159
The gap/question: did the direct-pathway facilitate movement and the indirect-pathway suppress it?
How the authors proposed the question: it’s a long-standing hypothesis in the field, with a few studies casting doubts on it at the time. Kreitzer was an expert in the basal ganglia field. Before this study, he had published several studies about the electrical properties of the D1- and D2- MSNs. The optogenetic tools are at the very early stage during 2009-2010. So this study was inspired by the intense interactions between these two lines of driving forces.
Brief summary: the authors found that optogenetically activating the D1-/ D2- MSNs increased/decreased the movements, respectively. The activation of D1-MSNs could rescue the movement deficits in Parkinson’s mouse model, suggesting a potential clinical treatment of Parkinson’s diseases.
The study was a milestone in the basal ganglia field. Although it created little new understanding, it confirmed the long-standing hypothesis, cleared the doubts, and turned it into a solid knowledge. So it’s also a big deal in the field.
The ongoing question(s) inspired by this study: how the outputs from the D1- and D2- MSNs control movements by modulating the down-stream brain areas?
