Effect of sensitization on somatostatin concentration and binding in cytosol from guinea pig airways.

In guinea pigs sensitized with 1 microgram ovalbumin together with 100 mg Al(OH)3, somatostatin levels were selectively increased up to two and 3 times in tissue extracts from trachea and bronchi, respectively, but not in lung as compared to controls. The increase of somatostatin levels observed in trachea and bronchi after sensitization was associated with a decrease in the binding capacity of both high- and low-affinity binding sites (without changes in the affinity values) in the corresponding cytosolic fractions. These results suggests that an increase in airways somatostatin content may be involved in the pathogenesis of anaphylactic bronchoconstriction.