lmmunocytochemical distribution of serotonin and neuropeptide Y, NPY in mouse adrenal gland

Abstract

By the use of imrnunocytochetnicd staining methods. we studied the morphology and distribution of SHT and NPY immunoreactive cells and fibres in the mouse adrenal gland. The 5HT-immunoreactive cells were numerous and widely localized in the medullar tissue. These cells were arranged in three cellular types with regard to their morphological and immunocytochemical features. One of them showed cells with polygonal shape, being intensified like the typical medullary chromaffin cells. These imniunoreactive cells were observed arranged in medullar islets. The second SHT-inimi~noreactive celular type was constituted by cells with polygonal shape and strong immunoreactivity. The third one was formed by cells with irnmunoreactive prolongations. We found some islets of chromaffin nonirnmunoreactive cells surrounded by immunostained cells. We also observed some 5HT-imniunoreactive nerve fibres in the rnedullar tissue. NPY-like itlitnunoreactivity was detected in both chromaffin and ganglion cells in adrenal medulla. NPY-like imrnunoreactivity was also detected in nerve fibres at cortical level. In a few cases, we observed medullar SHT- and NPYinimunoreactive tissue in the adrenal cortex (monotremas).