Oral stimulation with drugs known to either increase (glyburide) or decrease (diazoxide) KATP channel activity produced corresponding changes in CPIR magnitude (experiment 8). Each test involved two sessions: one was conducted with a control solution and the other with an experimental solution. A: in the glyburide test, the control solution was 0.5 M glucose (Glu) and the experimental solution was 0.5 M glucose + 0.15 mM glyburide (GB). B: in the diazoxide test, the control solution was 1 M glucose and the experimental solution was 1 M glucose + 0.25 mM diazoxide (DZ). Within a given panel, we represent the results from each mouse as two points connected by a line. The Δ plasma insulin concentration reflects the change in plasma insulin concentration between measurements obtained at baseline and 5 min after a mouse initiated licking for the experimental or control solution. Within each panel, we compare the Δ plasma insulin concentration elicited by the control vs. experimental solutions (paired t-test, *P < 0.03).