Endothelial cell-mediated regulation of aldosterone release from human adrenocortical cells

Endothelial cells play an important role in the development and functioning of endocrine tissue and endothelial cell-derived factors have been shown to regulate mineralocorticoid release in bovine adrenal cells. In the present study, we analysed the role of human endothelial cells in the synthesis and release of aldosterone from adrenocortical cells (NCI-H295R). Endothelial cell-induced aldosterone release was rapid and lasted as a long-term effect over a period of 48 h. This stimulant effect was influenced by the duration of endothelial cell conditioning and decreased linearly with increasing dilutions of the conditioned medium. At the molecular level, an increase in the mRNA transcripts of aldosterone synthase and StAR could be observed. Cellular interaction with endothelial cell-factors enhanced the activation of CRE, and the promoter activity of both StAR and SF-1 reporter genes. In conclusion, human endothelial cells are important intra-adrenal regulators of human aldosterone synthesis and release.