Entry into the brain and subsequent activation of GLP1-R was more rapid when the agonist was given IP compared with subcutaneously (SC), the usual route of administration for patients with diabetes, at 30 mins (****p < 0.0001 IP vs SC) and 2 h (**p = 0.0024 IP vs SC) (Fig. 3B). This evidence concerns the gene GLP1R and diabetes mellitus.