Rudolph Fanska

Anomeric Specificity of Glucose-Stimulated Insulin Release: Evidence for a Glucoreceptor?

The effects on insulin secretion of α and β anomers of D-glucose were studied in the in vitro perfused rat pancreas. Both phases of insulin release showed consistent stereospecificity for α-glucose; this specificity indicates an action of glucose independent of intracellular glucose metabolism.

Effect of age of rat on development of hepatic carriers for bilirubin: A possible explanation for physiologic jaundice and hyperbilirubinemia in the newborn☆

Abstract A metod is described for measuring the level of proteins found in hepatic cytosol which bind bilirubin and sulfobromophthalein (BSP). The method is based on the competitive binding of either pigment between the carrier proteins and highly cross-linked dextran particles. Most binding activity was found in the adult rat liver, which contained 7–10 times that of the adult brain, kidney, spleen, or muscle. Binding activity in fetal rat liver was 25–35 per cent of the adult level for either bilirubin or sulfobromophthalein. Adult levels in the liver were not attained before 30 days postpartum, while the small amount of activity in other tissues was unchanged with age. High concentrations of BSP displaced bilirubin from the carriers, indicating common binding sites and a large capacity for adult liver to bind both pigments. The immaturity of a carrier system for bilirubin shown in the newborn rat may provide a partial explanation for the physiologic jaundice and hyperbilirubinemia often observed in newborn humans.