Common textbooks of endocrinology envisage the adrenal cortex and the adrenal medulla as two functionally separate systems that are regulated independently from one another. Even worse, the mononuclear cells that are present within the normal human adrenal gland have been largely neglected or regarded as innocent bystanders. In this review we would like to draw attention to the close morphological and functional interplay between these systems and to propagate the notion that there is a meaningful cross-talk between the sympathico chromaffin system, the hypothalamus-pituitary-adrenocortical axis and the immune system at the level of the peripheral gland.
Morphological evidence for an interaction between the adrenal medulla and the adrenal cortex
The location of chromaffin cells within the adrenal cortex has been described in different species (1, 2), including humans (3). We were able to provide evidence, via specific immunostaining of chromaffin cells with antibodies to synaptophysin or chromogranin A, that in