Immunohistological studies for gastrointestinal and other hormones in acth-secreting adenomas.

Eighty-nine ACTH-secreting pituitary adenomas from patients with Cushing's disease or Nelson's syndrome were investigated by immunohistochemical methods for their content of gastrin, cholecystokinin (CCK), vasoactive intestinal peptide (VIP), bombesin, substance P, and ubiquitin as a marker for intercellular fibrils and hyalin and D11 as a marker for adrenocortical tissue. In contrast to in vitro studies reported in the relevant literature, we did not find significantly positive percentages (more than 10% of adenoma cells) for gastrin and CCK. VIP and bombesin were demonstrated in one adenoma. Among the adenomas examined, ubiquitin was found in 15% and D11 in 75%. ACTH was present in 99%, pro-γ-MSH in 21 %, β-endorphin in 13%, enkephalin in 4%, and α-subunit in 11.5%. The significance of the findings is discussed.