Fig. 2. The degree of selective neuronal hypoplasia is sustained as a function of age in the submucosal plexus of Cdnf^−/− mice while in the myenteric plexus the age-dependent decline is similar with no hypoplasia compared to Cdnf^+/+ mice;

(A) Transcripts encoding CDNF are expressed in stomach, intestine and colon of the murine gut at P7 but are absent in Cdnf^−/− mice. (B) Neuronal densities per mm² of plexus in the ileal submucosal plexuses, and (C) in the myenteric plexus in Cdnf^−/− mice (magenta solid line) and Cdnf^+/+ mice (blue solid line) are plotted as a function of age. The neuronal densities in the submucosal plexus are significantly lower in Cdnf^−/− mice than in Cdnf^+/+ mice at each age examined; [B] 2 way ANOVA F(2, 437) = 22.94. There is however some compensation between 1.5 and 11 month of age in Cdnf^−/− mice which does not occur in the Cdnf^+/+ mice; [C] in contrast in the myenteric plexus the decline as a function of age is similar in Cdnf^−/− and in Cdnf^+/+ mice without compensation between the genotypes. The numbers of animals were 3 Cdnf^−/− and 3 Cdnf^+/+ for 1.5 month-old mice; 6 Cdnf^−/− and 6 Cdnf^+/+ for 3 month-old animals; 7 Cdnf^−/− and 7 Cdnf^+/+ for 9–12 month-old mice; (D) Immunocytochemical detection of neurons using antibodies to HuC/D in whole mount laminar preparations of the ileal submucosal plexus in Cdnf^+/+ (D₁-D₃) and Cdnf^−/− mice (D₄-D₆) (scale bar, 32 μm).