Abstract
A newly developed in vivo method, using the ob-ob strain of obese-hyperglycaemic mice with permanently very high serum insulin values, makes it possible to detect more prolonged serum insulin lowering properties than in normal animals. Two newly synthesized analogues of somatostatin, D-alanine-somatostatin and des-alanine-des glycine-des-amino-somatostatin produced a more prolonged and greater decrease in the serum insulin values of ob-ob mice than did somatostatin. Our new in vivo method makes it possible to investigate the duration of insulin suppression of new derivatives.