Endogenous insulin secretion in the rat following injection of anti-insulin serum

Abstract

Rats were injected with known quantities of guinea pig anti-insulin serum and Il25-labeled human serum albumin. From the rates at which the injected antibodies were neutralized in the plasma and their volumes of distribution, it was concluded that the normal rat can secrete endogenous insulin at maximal rates of about 6 mU/100 g body wt per min. Injected antibodies were neutralized by endogenously secreted insulin, for their disappearance was prevented in the normal animal by mannoheptulose and did not occur in the alloxan-diabetic rat. Quantitative interpretation of the rates of antibody neutralization in terms of endogenous insulin secretion is subject to assumptions which are amenable to experimental proof but should not detract from the potential and simplicity of this method for the study of insulin secretion in vivo.