Monoamine Oxidase Type B is Localized to Mitochondrial Outer Membranes in Mast Cells, Schwann Cells, Endothelial Cells and Fibroblasts of the Rat Tongue

Abstract

We have used immunohistochemistry to examine the subcellular localization of monoamine oxidase type B (MAOB) in the rat tongue. Light microscopy showed that MAOB-immunoreactive structures were present in connective tissues. Electron microscopy revealed that MAOB immunoreactivity was localized to the outer membranes of mitochondria in mast cells, Schwann cells, capillary endothelial cells and fibroblasts. The present study is the first to immunohistochemically reveal the intracellular localization of MAOB in tissues outside of the central nervous system. Possible functions of MAOB in these cells are discussed.