In fresh frozen pancreatic tissue samples from six gastric-bypass surgery patients suffering from severe postprandial hyperinsulinemic hypoglycemia GLP-1R density was evaluated in vitro using the standardized autoradiography method and compared with normal pancreas and with pancreatic insulinoma tissues (Reubi et al. 2010). The gene discussed is GLP1R; the disease is hyperinsulinemic hypoglycemia.