Fig. 1.

Mouse small intestinal mucosa: glucagon-like peptide (GLP)-1 and somatostatin (SS) cells are found in close proximity, GLP-1 receptors are present on D-cells, and both D- and L-cells show SS binding. A: representative images showing immunohistochemical staining of GLP-1 (green) and SS (red) positive cells in the proximal small intestine, female mice, n = 17. B: immunohistochemical staining of the GLP-1 receptor (black arrow) and immunohistochemical staining of SS-positive cells (white arrow) on the same slide, female mice, n = 8. C: left: autoradiography before immunohistochemical staining showing grains representing ¹²⁵I-labeled SS-28, male mice, n = 3. Right: immunohistochemical staining of GLP-1 (solid black arrow) in combination with autoradiography showing grains of ¹²⁵I-labeled SS-28 (punctuated black arrow). D: left: the same as C, but with immunohistochemical staining of SS-positive cells, male mice. Right: The same as C but with immunohistochemical staining of SS-positive cells. ab, antibody. n = 3. Bar = 50 µm.