Pure synthetic bile salts release immunoreactive secretin in man

When 20 ml of 50 mmol/l pure synthetic bile salts (pH 6.5), of approximately the same composition as human bile, were infused into the duodenum of six healthy volunteers over 5 min during constant gastric aspiration, plasma immunoreactive secretin increased from 2.5 +/- 0.4 pmol/l to 3.6 +/- 0.5 pmol/l at 10 min (p < 0.025). Gastric acid secretion was not increased. No effect was seen when the same amount of physiological saline was infused under the same conditions in another group. It is concluded that bile salts in an amount and composition corresponding to that in the human gallbladder is able to release immunoreactive secretin from the human intestine.