Figure 3. β Cell mass.

(A) The group receiving HFD for 9 days developed a significantly greater β cell mass compared with controls fed 17% fat standard chow. However, with longer exposure to the HFD, there were progressively smaller increases in β cell mass after 18- and 28-day HFD. Return to regular diets did not alter β cell mass in any of the 3 groups whose HFDs were reversed to regular chow diets. Reverse indicates reversal to regular diet after 9, 18, or 28 days of high-fat diet. (B) Quantitative determination of pixel intensity for insulin-specific immunofluorescent signal measured in pancreatic sections from ZDF controls, HFD 9 days, and Reversed 9 days animals. Morphometric measurements were performed on 57, 64, and 73 sections per animal group, respectively. Two-way ANOVA, ***P < 0.005; ****P < 0.0001.