GCG and type 2 diabetes mellitus: Here, we tested glucose indexes, insulin tolerance, and GLP-1 concentration, under different GI peristalsis conditions, to study the relationship between glucose homeostasis and changed GI transit, seeking to understand the role of GI transit in alleviating diabetes after IT, in Goto-Kakizaki (GK) rat model (16), the most widely used nonobese animal model of T2DM.