SIDT2 and hyperinsulinemic hypoglycemia, familial, 4: To delve further into the relationships between Sidt2 deficiency and insulin secretion, insulin secretion disorder, and β-cell dedifferentiation, we established an in vitro model using octreotide (Oc), which is an inhibitor of insulin secretion, in INS-1 cells (Fig. 8, J and P).