GHRL and Insulin resistance: These Goto Kakizaki rats (n = 21) were randomly assigned into three groups: SG, sham SG, and pair-fed (PF) group, whose weight, food intake, oral glucose tolerance test, insulin tolerance test, plasma insulin, homeostasis model assessment for insulin resistance (HOMA-IR), ghrelin, and glucagon-like peptide-1 (GLP-1) were measured.