Fig. 9.

GGF selectively reduces Schwann cell death in the ventral root in both normal and NMDA-treated embryos. In controls, doses of GGF (5 μg) on E5 and E6 significantly decrease Schwann cell PCD, whereas other growth factors or neutralizing antibodies to p75 and NGF are ineffective (A, B). After NMDA (1 mg) treatment in ovo on E7 plus GGF (5 μg), Schwann cell death is not significantly reduced on E7.5 (C). However, after administration of a second dose of GGF at E7.25, ∼50% of Schwann cells are rescued from NMDA-induced cell death (D). Bars represent the mean ± SEM and the number of embryos is indicated within bars.