Leptin and islet cotherapy improves glucose tolerance. A: OGTT on day 20 after a 6-h fast in mice transplanted with islets with or without leptin and untreated diabetic (sham-vehicle)
mice, leptin-treated diabetic (sham-leptin) mice, and nondiabetic controls. B: Because some mice had blood glucose levels over the limit of detection after gavage, blood was collected at 10 and 20 min
for plasma glucose measurement. C: Plasma insulin levels after gavage. The limit of detection (0.188 ng/mL) is indicated by a broken horizontal line. Only
nondiabetic and 300 islets-vehicle groups had detectable plasma insulin levels at any given time. The remainder of mice were
assigned values of 0.188 ng/mL. Data are presented as mean ± SEM (n = 3–5). *P < 0.05. †P < 0.05 vs. nondiabetic controls. ‡P < 0.05 vs. sham-vehicle controls. NS, not significant.