EVIDENCE FOR ANALOGUES OF INSULIN IN HUMAN SERUM
The serum samples taken at 60 minutes after 50-gram oral glucose load from 6 cases of adult onset diabetic patients, a borderline case of diabetes mellitus and four healthy adult volunteers were subjected to extraction with acid-alcohol and gel filtration on the Bio-Gel P-30 column (1.6 x 90 cm). The fraction sizes of 2.0 ml and 4.05 ml were employed. Each of the fractions was radioimmunoassayed for immunoreactive insulin (IRI) after lyophilization and following results were obtained. 1) There are two groups of insulin in human serum, and each group could be separated more than two subgroups. 2) Adult onset diabetic subjects on diettherapy show the higher level of Peak I and Peak II than normal subjects. 3) Existence of these analogues of insulin in human serum are reported firstly, but it's physio-pathological significances remained to be verified.