Statistical analysis of the effects of the various drugs on DN number in Ddc-Gal4>DJ-1A RNAi flies. A: The numbers of DNs in the DMC of drug-treated 25-day-old Ddc-Gal4>DJ-1A RNAi flies was determined by TH-immunostaining of paraffin brain sections. These were compared with untreated Ddc-Gal4>DJ-1A RNAi flies or control Ddc-Gal4/+ flies with or without drug treatment. Animals were raised at 25°C. B: The numbers of DNs in the DMC of 25-day-old Ddc-Gal4>DJ-1A RNAi and Ddc-Gal4>DJ-1A RNAi+hDJ-1 flies with or without celastrol treatment (20 μg/ml) were determined by whole-mount TH-immunostaining. Animals were raised at 29°C. Note that at 29°C the DJ-1A RNAi effect is stronger than 25°C. Results are the mean ± SD of 8-25 sectioned heads for each genotype and drug treatment. **: P < 0.01 in ANOVA with Dunnett's post test.