endocrine gland mesoderm-derived structure abdomen element adrenal/interrenal gland This gland can either be a discrete structure located bilaterally above each kidney, or a cluster of cells in the head kidney that perform the functions of the adrenal gland. In either case, this organ consists of two cells types, aminergic chromaffin cells and steroidogenic cortical cells[GO] adrenal/interrenal gland structure with developmental contribution from neural crest