Fig. 4.

Pretreatment with Mito-Q₁₀ restores dopamine levels in MPP⁺-treated neuronal cells. (A) MDNs were treated with various concentrations of MPP⁺. After the termination of incubation, the cells were washed three times with DPBS and lysed in 200 μl of 0.1 M perchloric acid. Dopamine levels were determined from 50-μl aliquots of clarified supernatant using an HPLC method with amperometric–CoulArray detection and a C18 reverse-phase column and TM-50 solvent (flow rate, 0.6 ml/min) as described under Materials and methods. Dopamine levels were normalized to the total protein and the values were calculated using the dopamine standard. (B) Dopamine levels were determined after treating MDNs with MPP⁺ (25 μM), MPP⁺ plus Mito-Q₁₀, and Mito Q. Data shown are the means±SD of three separate experiments. **P<0.01 compared to controls; #P<0.01 compared to MPP⁺-treated group.