Figure 4.

Blockade of p75^NTR in MCM prevents activation of caspase 3/7 but not caspase 8. MNs were treated with the p75^NTR antibody, protein extracts were collected, and caspase activity was analyzed. A, Caspase 8 activity was measured in MCM- and ACM-treated MNs in response to p75^NTR inhibition. No change in the caspase 8 activity of ACM-treated MNs in response to p75 inhibition was observed; however, there was a slight, but statistically insignificant reduction in the caspase 8 activity of MCM-treated MNs in response to p75^NTR inhibition. B, Caspase 3/7 activity was measured in MCM- and ACM-treated MNs in response to p75^NTR inhibition. No change in the caspase 3/7 activity of ACM-treated MNs in response to p75^NTR inhibition was observed; however, the caspase 3/7 activity of MCM-treated MNs in response to p75^NTR inhibition was reduced by 60%. Data are expressed as a percentage of control CM (**p < 0.01; ANOVA with Tukey–Kramer post hoc analysis; n = 5).