Figure 1.

Experimental design. A, Young (3 months old) male rats received two intrastriatal injections of α-syn PFFs or PBS and electrode implantation into the STN during the same surgical session. B, Half of each treatment group was randomly assigned to receive continuous INACTIVE (stimulation never turned on) or ACTIVE stimulation. C, Outcome measures include quantification of inclusions and ELISA probing for BDNF, quantification of MHC-IIir microglia, intensity, size and complexity of astrocytes, and validation of electrode placement (Kluver–Barerra) and validation of inclusion formation (proteinase K digestion). D, Time points of stimulation interval and euthanasia were determined according to the period of peak inclusion formation (1–2 months, red), and microglial activation (2 months, blue) before overt loss of TH phenotype (2+ months, yellow) and degeneration of SNpc neurons (4–6 months, green). Red bars represent period of stimulation for each set of experiments.