Figure 7.
BDNF pretreatment of BF neurons does not protect against pro-NGF-induced apoptosis. A, BF neurons were grown in the presence of BDNF (10 ng/ml) for 5 d and treated overnight with pro-NGF alone, or in the presence of anti-p75NTR or anti-NGF as in Figure 1. Data are expressed as mean percentage of control ± SEM in triplicate cultures from four independent experiments (n = 12). The asterisks indicate values different from control at p < 0.05. Veh, Vehicle; mNGF, mature NGF. B, Western blot demonstrating that cleavage of caspase-3 was induced only by proneurotrophins and was not blocked by pretreatment with mature BDNF. The blot was stripped and reprobed for tubulin. C, Control. C, BF neurons were cultured on slide wells and treated with BDNF and pro-NGF. Neurons were double immunostained for full-length TrkB (anti-TrkBin) (top) or P-Trk (bottom) and p75NTR, and labeled with Hoechst to identify apoptotic nuclei. Scale bar, 10 μm.