The utility of [11 C] dihydrotetrabenazine positron emission tomography scanning in assessing β-cell performance after sleeve gastrectomy and duodenal-jejunal bypass

Background The aim of this study was to evaluate the effect of sleeve gastrectomy (SG) and duodenal-jejunal bypass (DJB) on glucose homeostasis and to evaluate the utility of positron emission tomography (PET) scanning for assessing β-cell mass. Methods Goto-Kakizaki rats were divided into 4 groups: control, sham, SG, or DJB. Oral glucose tolerance, insulin, and glucagon-like peptide-1 (GLP-1) were measured before and after surgery. Before and 90 days after treatment, [11 C] DTBZ micro PET scanning was performed. Results The control and sham animals gained more weight compared with SG and DJB animals ( P ≤ .05). Compared with control animals, the glucose area under the curve was lower in DJB animals 30 and 45 days after operations ( P ≤ .05). At killing, GLP-1 levels were greater in the DJB group compared with sham and SG ( P ≤ .05), whereas insulin levels were greater in both DJB and SG compared with sham ( P ≤ .05). With PET scanning, the 90-day posttreatment mean vesicular monoamine transporter type 2 binding index was greatest in the DJB animals (2.45) compared with SG (1.17), both of which were greater than baseline control animals (0.81). Conclusion In type 2 diabetic rodents, DJB leads to improved glucose homeostasis and an increase in VMAT2 density as measured by PET scanning.