Abstract
The distribution and break-down of insulin-I131 in rats under various changes in carbohydrate metabolism was studied. An intravenous glucose load exerted no detectable effect other than to reduce renal radioactivity. Intravenous fructose markedly reduced renal precipitable radioactivity, and increased hepatic and muscle radioactivity. Intraperitoneal glucose or fructose has the same effects as intravenous fructose but to a lesser degree. Alloxan diabetic animals concentrated more precipitable radioactivity in the liver and blood. Phloridzin exerted no effect on insulin distribution and degradation. Fasting effected little change; there was some decrease in renal and some increase in hepatic precipitable radioactivity. The limitations and implications of the study are discussed.