(A) Images of insulin injection in three different regions of the GI tract compared to subcutaneous administration. Clockwise from upper left: skin, stomach, colon, and duodenum. Representative images of the injections are shown. (B) Time in minutes to observe a drop in blood-glucose as a result of injection of insulin in the various GI tissue and skin. The median, 25th, and 75th percentiles are given. The whiskers indicate the most extreme data points. (C) Representative plots of normalized blood-glucose with time as a result of insulin injection subcutaneously, or through the stomach, duodenum, or colon. (D) Time in minutes to observe a drop in blood-glucose as a result of injection of insulin in the various GI tissue and skin. Averages and standard deviations are given. (*) indicates statistical significance compared to skin based on a multiple comparisons test from the ANOVA (p < 0.008).