Cyclic-AMP in human lung preparations

Cyclic-AMP levels in unaffected and affected cancerous portions of human lung preparations were determined by measuring displaced 3H-cyclic-AMP from the specific binding protein by unlabeled ligand. The levels of cyclic-AMP in unaffected portions of human lungs ranged between 52-116 pmoles/g protein. Significantly higher levels of cyclic-AMP were found in lung samples affected with squamous cell carcinoma, adenocarcinoma and malignant melanoma with the mean values being 251, 290, and 509 pmoles/g protein, respectively. On the other hand, a decrease in the level of cyclic-AMP to 39 pmoles/g protein was observed in portions of lungs affected with granuloma. These results suggest that the level of cyclic-AMP in lung tissue may reflect the malignant or benign nature of the pulmonary disease.