Comparison of Disappearance from Plasma of Insulin I 131 and of Insulin-Like Activity. ∗

Summary

Plasma decay curves were determined in diabetics and normals after the injection of a mixture of insulin I¹³¹ and crystalline insulin. The general forms of the curves as determined by bioassay and assay of radioactivity were similar, consisting of an initial rapid component and a late slower component. Insulin I¹³¹ tended to overestimate the half life of disappearance determined by bioassay of insulin-like activity.