secretin se·cre·tin (sĭ-krēt'n)
A polypeptide hormone produced in the duodenum, especially on contact with acid, that stimulates secretion of pancreatic juice.
a digestive hormone secreted by the wall of the upper part of the small intestine (the duodenum). Its secretion is stimulated when acid from the stomach or digested protein bathes the mucous tissue of the duodenum. Secretin, a protein of low molecular weight, evokes the discharge of fluid and bicarbonate ions from the pancreas; it also promotes the secretion of bile from the liver.
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