Abstract
Institut für Pharmakologie und Toxikologie, Universität Göttingen, Robert-Koch-Strasse 40, D-3400 Göttingen, Germany (Received 17 January 1978) Hyperinsulinaemia caused by female sex hormones has been attributed to increased insulin secretion by the pancreatic β-cells (Costrini & Kalkhoff, 1971; Hager, Georg, Leitner & Beck, 1972), but investigation of this hypothesis has been hampered by methodological difficulties. Treatment of the rat with female sex hormones may affect quantitative and qualitative yields of pancreatic islets after collagenase digestion of the pancreas and may increase the glucose-induced insulin release from the islets when the number of islets, but not the protein content, is chosen as the reference parameter (Costrini & Kalkhoff, 1971). Similarly, treatment with female sex hormones may affect the contamination of pancreatic islets with non-islet cells and therefore alter the islet protein content. Since protein content is used as a reference parameter, values for the rate of release of insulin from the pancreatic