Secretion of endothelin-1 and adrenomedullin by SW-13 human adrenocortical carcinoma cells

The adrenal medulla and pheochromocytomas are known to secrete various neuropeptides and vasoactive peptides. On the other hand, the production and secretion of peptides by adrenocortical tumors have not been studied in detail. The study reported, here therefore set out to examine these two functions for two vasoactive peptides, endothelin-1 (ET-1) and adrenomedullin (ADM) in SW-13 human adrenocortical carcinoma cells by radioimmunoassay and Northern blot analysis. Both immunoreactive ET (irET) and irADM were detected in the culture medium of SW-13 cells. Northern blot analysis showed the expression of ET-1 and ADM mRNAs in SW-13 cells. On the other hand, no significant amounts of calcitonin-gene-related peptide, corticotropin-releasing-hormone, neuropeptide Y or urocortin were secreted by SW-13 cells. This study has shown that ET-1 and ADM are the two unique vasoactive peptides that are produced and secreted by adrenocortical carcinoma cells.