Plasma Protein VII. Site of Degradation of Serum Albumin.

Abstract

1. Experiments have been carried out to show that serum albumin labeled with I¹³¹ passes from the circulation of rabbits into the duodenum. 2. Following injection of albumin-I¹³¹ the presence of TCA-in-soluble activity in a solution passed through the lumen of isolated section of intestine can be shown. 3. In other experiments of a somewhat different type, the same transfer has been shown. 4. Material transported appears to be albumin since it is precipitated with TCA, the precipitate is soluble in 95% alcohol (like similar precipitate of pure serum albumin), and the soluble material possesses the same electrophoretic mobility as albumin in experiments carried out on paper. 5. Approximate calculations indicate that if this type of transfer occurs in a considerable part of the gastro-intestinal tract, then the enzymatic breakdown of serum albumin so transferred could account for most of the serum albumin breakdown which occurs in vivo.