A: plasma glucose concentrations at all time points during GTT in PL- and RG-treated groups. 1, CON; 2, postnatal growth restriction (PNGR); 3, intrauterine growth restriction (IUGR); and 4, IUGR + PNGR. *P < 0.0001 and **P < 0.006, RG vs. PL is significantly higher. †P < 0.02 ad ††P < 0.0001, RG vs. PL is significantly lower. B: plasma insulin concentrations at all time points during GTT in PL- and RG-treated groups. 1, CON; 2, PNGR; 3, IUGR; and 4, IUGR + PNGR. The scale of the ordinate was adjusted to show the lower values in PNGR and IUGR + PNGR groups. Holm-Sidak test shows a significant decrease in RG CON and RG IUGR vs. corresponding PL groups: *P < 0.0001 **P < 0.004, and ♦P < 0.001. C: area under the curve (AUC) for plasma insulin concentration during GTT. Two-way ANOVA revealed a significant effect of RG treatment (F = 34.512, P < 0.001), early nutrition (F = 12.729, P < 0.001), and RG treatment × early nutrition (F = 12.139, P < 0.001). Holm-Sidak test revealed significant decrease in insulin AUC for RG CON and RG IUGR vs. the corresponding PL group (*P < 0.0001) and ♦P < 0.0001 for PL PNGR and PL IUGR + PNGR vs. the PL CON.