[Immunohistochemical demonstration of cells containing melatonin and N-acetylserotonin]

The presence of cells containing N-acetylindolylalkylamines in the acini of the pancreas, at the border of the cortical and cerebral layer of the adrenal glands, under the capsule of the liver and in the vascular wall was shown by means of the immunohistochemical method with the use of specific antisera to melatonin and N-acetylserotonin. Further studies are necessary for the morphological identification of the type of these cells.