Fig. 1.

A: individual blood glucose concentrations up to 300 min before and 90 min after intraperitoneal injections of saline (dashed lines) or insulin (solid lines) at 0 min. Note that three insulin-injected animals maintained euglycemia throughout (heavy dashed lines). These animals were included in the euglycemic group for data analyses. Euglycemic and hypoglycemic ranges are indicated by the light and dark gray shadings respectively. B: mean (+SE) blood glucose concentrations immediately before (0 min, open bars), 30 min (gray bars), and 90 min (black bars) after intraperitoneal injections of saline or insulin. Animals that became hypoglycemic did so within 30 min of intraperitoneal insulin injections (P < 0.001), with blood glucose concentrations declining further by 90 min (P < 0.002 compared with 30 min).