Figure 4.

Neuroprotection against 6-OHDA toxicity following delayed subchronic intranigral administration of 2R,4R-APDC is associated with reduced numbers of activated microglia in the SNc. Representative photomicrographs (×40) of DAB/peroxidase staining for OX-6, a marker of activated microglia in the SNc from each treatment group (scale bar 200 μm.). (a) 6-OHDA + vehicle, unlesioned SNc, (b) 6-OHDA + vehicle, lesioned SNc, (c) 6-OHDA + 2R,4R-APDC (10 nmol) unlesioned SNc, (d) 6-OHDA + 2R,4R-APDC (10 nmol) lesioned SNc. Note the increase in intensity of OX-6 staining and the increase in OX-6+ cells displaying morphology of activated microglia in the lesioned SNc of vehicle-treated animal, which appears markedly reduced in animals treated with 2R,4R-APDC.