Fig. 1. Enhanced cell death in the SVZ-RMS of NCAM-deficient animals. (A) Photomicrographs of HE-stained sagittal sections illustrating the enlarged SVZ-RMS in NCAM-deficient (NCAM KO) as compared with WT mice. (B) TUNEL assay (lower panels, green fluorescence) reveals that apoptosis is increased in the SVZ-RMS of mice lacking NCAM (right) as compared with WT (left). Hoechst counterstaining on the same sections (upper panels) shows dying cells located in the SVZ-RMS but not in neighboring areas. These pictures correspond to the boxed regions in A. (C) Quantification of the density of TUNEL⁺ cells in WT and NCAM^-/- brains demonstrates a significant increase in cell death in the SVZ and RMS of NCAM mutant animals. ^*, P<0.05 (two-tailed unpaired t-test). CC, corpus callosum; V, lateral ventricle; St, striatum. The limit between SVZ and St is represented by the dashed line. Scale bar: 1 mm in A; 100 µm in B.