Data points represent means ± s.e.m. of the blood glucose concentration in sham (n = 7) and CSNX (n = 7) animals. Insulin infusion, represented by the horizontal bar, began at time 0, was maintained for 120min and caused significant (P < 0.0001, ANOVA) and similar (P > 0.15, ANOVA) amplitude falls from preinfusion levels of blood glucose in both groups of animals.