FIGURE 1.

Interaction of minocycline with PON or ^•NO. A, minocycline, in the concentrations indicated, was preincubated with the PON donor Sin-1 (50 μm), followed by the addition of DHR 123 (1 μm). Rhodamine generated from DHR 123 was detected in a fluorescence reader. Alternatively, minocycline was pretreated with the ^•NO donor Spermine-NONOate (10 μm), and ^•NO was measured by a ^•NO-selective electrode over a period of 100 s. B, human dopaminergic neurons (LUHMES) were exposed to the PON-generating Sin-1 (100 μm) or the ^•NO donor Spemine-NONOate (100 μm) in the presence of various concentrations of minocycline or left untreated (control, contr.). After 4 h, the incubations were terminated by medium removal and lysis of the cells. The amount of protein and GSH were determined in the lysates. The data are expressed as the means ± S.D. of quadruplicate samples. The statistical significance was determined by one-way ANOVA followed by Bonferroni's post-hoc test. *, p < 0.05 versus 0 μm minocycline.