OBSERVATIONS ON THE INCORPORATION OF ³⁵S IN DUODENAL MUCOSUBSTANCES

Abstract

1. A method is described for preparing and collecting juice from duodenal fistule in rabbits. 2. Intravenous injection of Na 2 35 SO 4 into rabbits results in the rapid appearance of 35 S in duodenal mucous secretion obtained from fistulæ or in acute experiments. 3. Such secretion contains 35 SO 4 2‐ , mucosubstances containing 35 S‐sulphate ester groups, and a dialysable 35 S‐sulphate ester of unknown structure. 4. The proportion of ester 35 SO 4 to 35 SO 4 2‐ in duodenal secretion reaches a steady value 9 hours after injection of the isotope, the radioactivity of the blood having fallen to a very small value at this time. It is suggested that the mucous glands have the capacity to store 35 SO 4 2‐ in some form. 5. Injection of 35 S‐methionine results in the incorporation of the amino‐acid into the mucosubstances. No evidence of its conversion to 35 SO 4 2‐ was found in the duodenal secretion. 6. Cortisone has some slight effect on the incorporation of 35 SO 4 2‐ , but none on that of 35 S‐methionine, into epithelial mucosubstances of the rabbit duodenum.