Fig 7. N27-A cells are more sensitive to MPP+ toxicity than unpurified N27 cells, and nomifensine can block MPP+ induced toxicity.

Purified N27-A and unpurified N27 cells were cultured in 96-well plates at equal starting density. Two days after plating, cells were treated with 0–1000 μM of MPP+ for 24 hr. (A): Cell viability data from MTT assays showed that there was significantly greater cell death in N27-A cultures compared to that in N27 cultures after 100 μM to 1000 μM of MPP+ treatment (n = 12, *p<0.05). (B): After nomifensine pre-treatment, exposure to MPP+ did not significantly reduce cell viability in either N27-A or N27 cells, even when MPP+ reached 1000 μM (n = 12, p>0.3).