Figure 4

Expression of endocrine hormones in pancreata of wild type, Arx^-, Nkx2.2^-/- and Nkx2.2^-/-Arx^- newborns. Insulin (A-D), glucagon (E-H), pancreatic polypeptide (I-L), somatostatin (M-P) and ghrelin (Q-T) immunofluorescence-detection at P0. (D, H) Note that both beta- and alpha-cells lack in Nkx2.2^-/-Arx^- double-mutant mice (original magnification: 200×). (U-X) Co-detection of ghrelin and somatostatin in P0 pancreata of wild type, Arx^-, Nkx2.2^-/- and Nkx2.2^-/-Arx^- mice. Somatostatin⁺ cells and ghrelin⁺ cells label distinct cell populations in wild type (U), Arx- (V) and Nkx2.2-deficient (W) pancreata. (X) However, in Nkx2.2^-/-Arx^- double mutant mice a population of ghrelin⁺/somatostatin⁺ co-positive cells is detectable besides single-hormone-expressing ghrelin⁺ or somatostatin⁺ cells. Pictures in U-X were taken using confocal microscopy. Counterstaining with DAPI. (Y) Quantification of hormone producing cells (without PP-cells) in pancreata of wild type, Arx^-, Nkx2.2^-/- and Nkx2.2^-/-Arx^- mice at P0. Bars represent percentage of fluorescent cell area per total pancreatic area. n = 3 pancreas per genotype. Single-factor ANOVA coupled to Newman-Keuls test was applied and p-values < 0,05 were assessed as statistically significant compared to wild type. Statistical significance is achieved with the assumption of a normal distribution. Error bars represent SEM.