Immunoreactivity for β/A4 protein, but not for its precursor, in human chromaffin cells

• Published in: Brain research bulletin Vol. 37; no. 5; pp. 449 - 455
• Main Authors: Alonso-Cortina, V.L., González-Vázquez, L.O., Cabal, A., Esteban, I., Del Valle, M.E., Vega, J.A.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 1995; Elsevier Science
• Subjects: Adrenal gland; Adrenals. Interrenals; Aged; Amyloid beta-Peptides - metabolism; Amyloid beta-Protein Precursor - metabolism; Biological and medical sciences; Chromaffin cells; Chromaffin System - cytology; Chromaffin System - metabolism; Chromogranin A; Chromogranins - metabolism; Female; Fundamental and applied biological sciences. Psychology; Human; Humans; Immunohistochemistry; Male; Middle Aged; Morphology. Functional localizations; Nerve growth factor receptors; Neurofilament Proteins - biosynthesis; Neurofilaments; Neurons - metabolism; Receptors, Nerve Growth Factor - metabolism; S100 Proteins - metabolism; Vertebrates: endocrinology; β-Amyloid protein; β-Amylold precursor protein; Chromaffin cells; Human; Nerve growth factor receptors; Neurofilaments; Adrenal gland; β-Amylold precursor protein; β-Amyloid protein; Neurotrophin; Endocrine gland; Adrenal medulla; Nerve growth factor; Coexistence; Chromaffin cell; Gene expression; Amyloid precursor protein; Neurofilament; Immunoreactive form; β Amyloid protein; Biological receptor
• ISSN: 0361-9230; 1873-2747
• DOI: 10.1016/0361-9230(95)00022-7

The present study was designed to establish a) whether chromaffin cells of the human adrenal medulla express immunoreactivity for β-amyloid precursor protein (βAPP) and/or β-amyloid protein (β/A4); and b) whether cells expressing one or both of the above-mentioned proteins display immunoreactivity for the low- (gp75) and/or the high-affinity (gp140-
trkA) nerve growth factor receptor. To identify chromaffin cells and their supporting cells, chromogranin A, neurofilament proteins, and S-100 protein were studied in parallel. βAPP and β/A4 immunoreactivity (IR) was observed primarily labeling two different cell populations, without colocalization: βAPP IR was found in the adrenal cortical cells, which were mainly localized in the reticulate layer and in the blood vessel walls, whereas β/A4 IR was observed in the chromeffin cells.
Furthermore, supporting cells were also immunoreactive for β/A4, and sympathetic gangionic cells were immunoreactive for both βAPP and β/A4. Interestingly, clusters of cells expressing β/A4 IR also displayed gp75 IR and/or gp140-
trkA IR. Finally, all chromaffin cells (identified by chromogranin A IR) were immunolsbeled for the 200 kDa neurofilament subunit, but not for a phosphorylated epitope of this protein. These results demonstrate the occurrence of β/A4 IR, but not of βAPP, in the chromaffin cells of the human adrenal gland. The complementary distribution of amyloid-related proteins, and the possible involvement of neurotrophins in β/A4 metabolism are discussed.