Tohoku J. Exp. Med., 2004, 203(2)

Differential Localization of Brain-Type and Epidermal-Type Fatty Acid Binding Proteins in the Adrenal Gland of Mice

XIA YUN,¹ MOHAMMAD REZA NOURANI, SOHA ABDELKAWI ABDELWAHAB, NORIKO KITANAKA, YUJI OWADA, FRIEDRICH SPENER,² HIROO IWASA, AKIRA TAKAHASHI¹ and HISATAKE KONDO

Division of Histology, Department of Cell Biology, ¹Division of Neuro-Intravascular Disease, Department of Neuroscience, Graduate School of Medicine, Tohoku University, Sendai 980-8575, and ²Department of Biochemistry, Muenster University, Muenster, Germany

In immuno-light and -electron microscopy, brain-type fatty acid binding protein (B-FABP) is localized in the sustentacular cells enclosing the chromaffin cells in the adrenal medulla. This represents another new feature commonly shared by the sustentacular cells and ganglionic satellite cells, the latter of which has already been reported to localize this molecule, and suggests a common feature in lipid metabolism shared by the two cells enclosing peripheral neurons and paraneurons. On the other hand, epidermal-type fatty acid binding protein (E-FABP) is localized in two discrete cells in the adrenal gland: the one is a subpopulation of intra-adrenal macrophages which are intensely immunoreactive for F4/80, a marker of macrophages, and are rich in pleomorphic lysosomes. Because of their direct apposition to adjacent cortical endocrine cells and medullary chromaffin cells, the macrophages may be involved not only in phagocytosis of degenerating adrenal cells but also in exertion of some yet unknown effects on the endocrine function of the cortical and medullary cells via humoral factors such as cytokines which have recently been known to be secreted by macrophages. The other is a population of cells having scanty perikaryal cytoplasm poor in organneles and several thinny extended processes in the cortex and exhibiting weak immunoreactivity for E-FABP. The possible natures of these cells immunoreactive for E-FABP are discussed in view of a subpopulation of endothelial cells or the dendritic cells of antigen-presenting property.

keywords —— B-FABP; E-FABP; sustentacular cells; adrenal gland; immunohistochemistry

© 2004 Tohoku University Medical Press

===============================

Address for reprints: Yuji Owada, Division of Histology, Department of Cell Biology, Graduate School of Medicine, Tohoku University, 2-1 Seiryomachi, Aoba-ku, Sendai 980-8575, Japan.

e-mail: yowada@mail.tains.tohoku.ac.jp