Na+/HCO3- cotransporter is expressed on β and α cells during rat pancreatic development

Figure 2 Localization of NBC1 and amylase determined by immunofluorescence detection in different developmental stages of rat pancreas. Labeling of NBC1 antibodies was detected with an FITC (green)-labeled secondary antibody. Labeling of amylase was detected with a CY3 (red)-labeled secondary antibody on the same section. The overlap of NBC1 (green) and amylase (red) labeling creates orange color. NBC1 positive cells can be detected in pancreas sections at all time points tested. Specific NBC1 immunostaining is present at the basolateral membrane of acinar cells (I, arrow) and the plasma membrane of β cells (F, arrow). NBC1 positive cells make up a widespread proportion of the total cells at E18.5 (A-C) and there is an overlap between the NBC1 positive cells and cells marked with antibodies against amylase in pancreas of E18.5 (arrow). NBC1 positive messages decline to a low but detectable level in acinar cells in adult rat comparing with that of β cells, which apparently are strong positive signals (L, arrow). All of the primary magnifications are × 400. Insets, higher magnifications of the areas indicated by arrow in embryonic day (E)18.5, postnatal (P)7 and P14.