Fig. 5. Blockade of EphA/ephrin A interaction induced abnormal migration of olfactory cortex neurons. (A) Experimental procedures for EphA/ephrin A signaling blockade. (B,C) Migration patterns of GFP-positive cells in media containing Fc (B) or EphA3 (C). In Fc-containing media, the GFP-labeled neurons stopped at the PSB (arrows in B), whereas in the Eph-A3-Fc-containing media, the GFP-labeled neurons crossed the PSB and invaded the ventral part of the telencephalon (arrowheads in C). (D) Comparison of the number of GFP-positive cells in the ventral part of the telencephalon (the purple area) in Fc- and EphA3-treated telencephalon. Because in control (Fc treated) samples most of the GFP-positive cells aligned at 1.0-1.2 mm distant from the dorsal margin of the telencephalon, we marked this point as `prospective PSB' and compared with the number of GFP-positive cells ventral of this point. Data are presented as percentage of the labeled cells in the ventral telencephalon against the total number of labeled cells (mean±s.d. of four samples in each group). ^**P<0.01. r, rostral; c, caudal; d, dorsal; v, ventral. Scale bar: 500 µm.