Fig. 2

Insulin secretion and insulin resistance. a Plasma insulin levels at the beginning and the end of the infusion. b Insulin resistance was estimated as HOMA-IR. c β cell function was estimated as HOMA-β %. SAL (SAL group rats underwent 48 h infusions with saline); CHG (CHG group rats underwent 48 h infusions with 50 % glucose continually to keep the glucose concentration at 20 ± 0.5 mmol/l); AFG (AFG group rats underwent 48 h infusions with 50 % glucose intermittently so that blood glucose alternated between 5.5 ± 0.5 and 20 ± 0.5 mmol/l). Data are mean ± SD. n = 10/group. *P < 0.05 vs SAL