Purified human insulin and beef-pork glucagon were subjected to electrophoresis on cellulose acetate strips. Insulin was found to migrate rapidly towards the anode as a single band, while glucagon migrated slowly towards the anode in two distinct fractions. Virtually complete separation of the two hormones was achieved.
Electrophoresis of acid alcohol extracts of human pancreas revealed eight positively migrating bands. By means of densitometric, radioisotopic, and radioimmunochemical technics, fraction 2 was identified as the insulin-bearing fraction, and the area of fractions 7 and 8 as the glucagonbearing region. By gel filtration substantial quantities of the unidentified extraneous proteins, which make up the bulk of the pancreatic extract, were removed, thereby providing purer samples for electrophoresis.
The technic makes possible the rapid preparation of relatively pure samples of glucagon-free insulin and insulinfree glucagon from the pancreas of man and other species in quantities sufficient for laboratory studies. In addition, the characterization of the electrophoretic mobility of these hormones provides a new means by which they may be identified in unknown samples.
