A chromophil (syn. chromaffin) cell readily absorbs chromium salts which are used in histology to increase the contrast of samples for microscopy. Chromophil cells are mostly hormone producing cells containing so called chromaffin granules. In these subcellular structures, amino acid precursors to certain hormones are accumulated and subsequently decarboxylated to the corresponding amines, for example epinephrine, norepinephrine, dopamine or serotonin. Chromophil cells therefore belong to the group of APUD (amine precursor uptake and decarboxylation) cells. They are scattered throughout the whole body, but enriched in glands such as the hypothalamus, hypophysis, thyroid, parathyroid and pancreas.