Analysis of mRNA expression for steroidogenic enzymes in the remaining adrenal cortices attached to adrenocortical adenomas

Abstract

Design and methods: We have recently demonstrated that the adrenal cortices attached to aldosterone-producing adenoma (APA) contained microscopic subcapsular micronodules suggestive of active aldosterone production. In this study, we used in situ hybridization to investigate the mRNA expression of steroidogenic enzymes in the adrenal cortices attached to cortisol-producing adenoma (CPA) and clinically silent adenoma (non-functioning adenoma; NFA), in addition to APA. Results: Microscopic subcapsular micronodules, which were several hundreds of micrometers in size and spheroid in shape, were observed in the cortices attached to CPA and NFA, as well as APA, at high frequency. Most of the cortical nodules in zona fasciculata to zona reticularis showed a suppressed steroidogenesis in the cortices attached to adenoma, but some expressed intensely all necessary steroidogenic enzyme mRNAs for cortisol synthesis. Conclusions: It is thus necessary to keep in mind, on the occasion of subtotal adrenalectomy, that lesions with the potential to later develop into functional adrenocortical nodules may be present in other parts of the ipsilateral or contralateral adrenal cortices. © 2008 Society of the European Journal of Endocrinology.