Fig 1. Effect of proteasome and lysosome inhibition on TH protein level.

PC12 cells were treated with 1 μmol/L lactacystin (A), a specific proteasome inhibitor, or 5 nmol/L bafilomycin (B), a H⁺-ATPase inhibitor, at different times and TH protein level assessed by Western-blot as described under Methods. The blots were stripped and reprobed for GAPDH to assess protein loading. Signals from TH protein level were normalized to GAPDH levels. Each bar represents the mean ± SEM of 3 determinations from four separate cell culture preparations. * P < 0.05 as compared to basal.