Update on the corticomedullary interaction in the adrenal gland.

The adrenal gland is formed by the adrenal medulla and the adrenal cortex. Both tissues descend from different origins during embryonal development. While the chromaffin cells are derived from the neural crest, the adrenocortical cells stem from a cell condensation in the celomic epithelium. Already during adrenal organogenesis, close interactions between the two tissue types are necessary for the differentiation, morphogenesis and survival of the adrenal gland. Moreover, the communication between the chromaffin and adrenocortical cells ensures a regular function of the adult adrenal gland including the regulation of hormone synthesis and responses to stress. This is even more important since the cortical-chromaffin crosstalk is also relevant for the pathogenesis of different diseases. In the past decade, significant progress in the understanding of the cortical-chromaffin communication has been made. Here, we summarize the insights gained from in vitro studies, from animal models and from clinical observations.