||FIG. 3. Expression of BDNF mRNA in the developing Xenopus retina. Transverse sections through stage 40 (A) and 45 (B and C) retinas
hybridized in situ with a digoxygenin-labeled antisense Xenopus BDNF probe show specific cytoplasmic hybridization signals over cell
bodies in the ganglion cell layer (gcl) and the ciliary margin cells (cm). In some stage 45 retinal sections, one to two digoxygenin-labeled
cells were observed in the inner nuclear layer (inl) (B; arrowhead). Note the increase in both the intensity and number of digoxygeninpositive
cells in the gcl of stage 45, versus the stage 40, retina. Due to the conditions of the hybridization procedure (see Materials and
Methods), the specific cytoplasmic hybridization signal is excluded from the large cell nuclei. (D) Hybridization of a stage 45 retina with
a sense BDNF probe shows no hybridization signal. ipl, inner plexiform layer; onl, outer nuclear layer; opl, outer plexiform layer; pe,
pigmented epithelium. Dorsal is up, ventral is down. Scale bar, 50 mm.