concentrations were very low in the foregut ( antrum , 3.4 +/- 0.3 pmol/g ; duodenum , 1.1 +/- 1.5 pmol/g ) , higher in the distal small intestine ( ileum , 100 +/- 13 pmol/g ) and very high in the large bowel ( descending colon , 270 +/- 45 pmol/g ) .
C0013303
duodenum
C0021852
small intestine