Abstract
Rat serum proteins were labelled in vitro with a fluorescent dye, acid rhodamine B, C.I. No. 45100, using Chadwick's method. Labeled serum was injected intravenously in albino rats weighing 150-200 gm, in doses of 0.8 cc/100 gm body weight. Biochemical and histological findings indicate that there is an equilibrium among serum proteins, connective tissue (as temporary place for storage of these) and reticuloendothelial system, thyroid, ovary and renal tubuli contorti cells (as a place for prolonged deposit of serum proteins).