The isolation of the urogastrones - inhibitors of gastric acid secretion - from human urine.

It has been known for over thirty years that extracts of human urine could cause inhibition of gastric acid secretion. The active principle was called urogastrone and this has now been isolated using a series of twelve simple stages of partition, gel and ion-exchange chromatography. In fact two products were obtained, each in a yeild of less than 1 mg per 1 000 l urine, which represented an overall recovery of 3 - 5%. These materials were biologically indistinguishable, causing inhibition of gastric acid secretion in a variety of circumstances at doses of less than 1 mug/kg. The purified urogastrones were found to be acidic polypeptides composed of 53 and 52 amino acid residues with three internal disulphide bonds, and they differed by only one arginine residue. Neither threonine nor phenylalanine residues were present in the urogastrones.