STUDIES OF THE MECHANISM OF IRON ABSORPTION. I. IRON UPTAKE BY THE NORMAL RAT.

摘要: Abstract The mechanism of radioiron absorption was studied in intact rats. Small physiologic (20 μg) doses iron as ferrous sulfate were given to rats which then killed at intervals 1 minute 48 hours. Uptake radioactive by the upper small intestinal mucosa, its subcellular particles, and various other tissues measured. nonparticulate fraction homogenized mucosa further fractionated into protein nonprotein components, iron-binding materials isolated. Measurable uptake occurred within minute, major part had been completed less than hour. Two pathways found: (1) an early, rapid-transit form associated with amino acids glycine serine; (2) a later, slow-release bound nonferritin protein.