The presence of three regulatory peptides, corticotropin-releasing hormone, neuropeptide Y and endothelin-1, was studied by radioimmunoassay in the tumor tissue of an ACTH-secreting bronchial carcinoid. A 36-year-old female was admitted to hospital because of moon face, central obesity and hypertension. High levels of plasma ACTH and cortisol and urinary 17-OHCS and 17-KS were found. One mg dexamethasone did not suppress plasma ACTH and cortisol levels, but 8 mg did so slightly. Corticotropin-releasing hormone (100 μg. iv) stimulated plasma ACTH levels (0 min; 34.8 pmol/l; 30 min; 41.1 pmol/l). The computerized tomography showed the presence of a tumor in the right lung. This lung tumor was removed surgically and has been shown by microscopical examination to be a bronchial carcinoid with ACTH-positive cells. The tumor tissue concentrations of corticotropinreleasing hormone, neuropeptide Y and endothelin-1 were 3.34 pmol/g wet weight, 8.07 pmol/g wet weight and 0.92 pmol/g wet weight, respectively, although plasma concentrations of these three peptides were not elevated. Reverse phase high performance liquid chromatography showed that immunoreactive peptides in the tumor tissue were mainly eluted in the position of the standard peptides. These findings indicate that this case of ACTH-secreting bronchial carcinoid had high levels of corticotropin-releasing hormone, neuropeptide Y and endothelin-1 in its tumor tissue and suggested that these peptides may act locally, in a paracrine or autocrine manner, in the tumor.
Osamu Murakami, Kazuhiro Takahashi, Masahiko Sone, Kazuhito Totsune, Makoto Ohneda, Keiichi Itoi, Kaoru Yoshinaga and Toraichi Mouri
Kazuhito Totsune, Kazuhiro Takahashi, Osamu Murakami, Fumitoshi Satoh, Masahiko Sone, Makoto Ohneda, Yukio Miura and Toraichi Mouri
Totsune K, Takahashi K, Murakami O, Satoh F, Sone M, Ohneda M. Miura Y. Mouri T. Immunoreactive brain natriuretic peptide in human adrenal glands and adrenal tumors. Eur J Endocrinol 1996;135:352–6. ISSN 0804–4643
The presence of brain natriuretic peptide (BNP) in tissues of human adrenal glands and adrenal tumors was investigated by radioimmunoassay. Immunoreactive BNP concentrations were 0.203 ± 0.061 pmol/g wet tissue (mean ± sem) in normal parts of adrenal glands (cortex and medulla. N = 8), 0.205 ± 0.037 pmol/g wet tissue in pheochromocytomas (N = 8), 0.230 ± 0.062 pmol/g wet tissue in aldosteronomas (N = 11) and 0.180 ± 0.054 pmol/g wet tissue in adrenocortical adenomas with Cushing's syndrome (N = 4). Sephadex G-50 superfine column chromatography and reverse-phase high-performance liquid chromatography showed that most (> 70%) of the immunoreactive BNP in the normal part of adrenal glands was eluted in the position of human BNP-32. Sephadex G-50 superfine column chromatography of immunoreactive BNP in the pheochromocytoma and aldosteronoma showed four peaks: one in the position ofγ-BNP, one in the position of BNP-32, one between γ-BNP and BNP-32 and one in the smaller molecular weight region. The present study has shown that immunoreactive BNP is present both in normal human adrenal glands and in adrenal tumors. Multiple molecular forms of BNP were found to be present in the tumor tissues of pheochromocytoma and aldosteronoma.
Kazuhiro Takahashi. Department of Applied Physiology and Molecular Biology, Tohoku University School of Medicine, 2–1 Seiryo-machi, Aoba-ku. Sendai 980–77, Japan