Fig. 8. p75^NTR (A) and TßRII (B) immunoreactivity in consecutive cryosections of an E5 chick retina, as revealed by indirect fluorescent stains (p75^NTR, FITC/green; TßRII, CY3/red). TßRII immunoreactivity is distributed evenly, whereas p75^NTR staining is mainly observed in the prospective ganglion cell layer and optic fiber layer, as well as in the optic nerve. The main overlap of both receptors can be found in the optic nerve region, where most cells stain positively for both, p75^NTR and TßRII. on, optic nerve; ov, optic ventricle. Scale bar: 50 µm.