Effect of ligation of common bile duct on somatostatin levels and binding in cytosol of rabbit duodenal mucosa.

Rabbits with ligation of the common bile duct, of one and three weeks duration, showed a significant increase of somatostatin content in duodenal mucosa and plasma as compared with control animals. The increase of mucosal somatostatin was associated with a decrease in the binding capacity of both high- and low-affinity binding sites without changes in the affinity values in cytosol of duodenal mucosa. These findings suggest that the number of somatostatin binding sites is inversely related to local levels of the peptide and support the hypothesis of somatostatin regulating its own binding sites.