Figure 3

Insulin-, glucagon-, glucagon-like peptide-1 (GLP-1)-, and somatostatin- immunoreactive (IR) endocrine cells in pancreas from rats fed control (C), medium Maillard (MM)- and high Maillard (HM)-containing diets for 1 (1w) and 4 weeks (4w). (a–f) Pancreatic sections from rats after 4 weeks fed C (C 4w) or HM (HM 4w) diets were double immunostained for (a,b), insulin (green) and glucagon (red), (c,d) insulin (green) and GLP-1 (red), and (e,f) insulin (green) and somatostatin (red). The topographic distribution of endocrine cells, with central insulin-IR cells and peripherally located glucagon-, GLP-1- and somatostatin-IR cells is similar in all rats irrespective of diet. Notable is, however, that the number of GLP-1-IR cells is higher in the rat fed HM 4w (d), as compared to (c), the C 4w rat. Scale bar is 100 μm and applies to (a–f). (g,h) Cell counting revealed that the insulin:glucagon cell ratios were approximately 2 in all rats irrespective of if they were fed C, MM- or HM-containing diets for 1 week (g) or 4 weeks (h). (i,j) The insulin:GLP-1 cell ratios were approximately 1 in rats fed MM or HM diets at both 1 week (1w) and 4 weeks (4w), which was markedly lower than, approximately 2, in pancreas from C rats. (k,l) The insulin:somatostatin cell ratios were similar in all rats irrespective of diet. (m,n) Pancreatic sections double immunostained for insulin (red) and the homeobox protein Nkx6.1 (green) from rats fed C or HM diets for 4 weeks (4w). Note the selective nuclear expression of Nkx6.1 protein in all insulin-IR cells. Scale bar is 100 μm and applies to both m and n.