Figure 1: Neuroepithelial cell apoptosis in normal and NTD embryos.

(a) indicators of histological sectioning plane for b. E10.5 embryos were used for apoptosis detection. Red lines indicate the levels of sectioning shown on the right. For each embryo, five sections from top to bottom were chosen to detect apoptotic cells in the forebrain, midbrain, hindbrain and spinal cord were indicated in each picture. Scale bars: 300 μm. (b) representative TUNEL assay images showing apoptotic cells (red dots) in sections of the forebrain, midbrain, hindbrain and spinal cord. Cell nuclei were stained with DAPI (blue). Scale bars: 300 μm and 70 μm for the enlarged boxed areas. (c) quantification of TUNEL positive cells per section (three serial sections of each area per embryo, and three embryos from three dams were analysed) in the corresponding brain regions. ND, nondiabetic dams; DM, diabetic mellitus dams; NTD, exencephaly. *indicates significant difference (P<0.05) compared with the ND groups in one-way ANOVA followed by Tukey tests.