INTESTINAL MONOAMINE OXIDASE: LOCALIZATION, FUNCTIONS, ROLE IN PATHOLOGY

Monoamine oxidase is an enzyme whose functions and contribution to pathology have been so well studied in the brain, but remains unjustifiably for-gotten in other organs and tissues, despite the fact that it is far from organ-specific and even has its maximum activity in the periphery rather than in the CNS. Data on the activity of monoamine oxidase in the intestine are isolated and fragmentary. Publications of individual clinical cases with positive effects in the treatment of chronic inflammatory bowel diseases with monoamine oxidase inhibitors served as a starting point for the initiation of fun-damental research on cellular and animal models. Changes in the regulation and expression of the enzyme were found in some oncological diseases of the gastrointestinal tract, including gastric cancer and colorectal cancer. This review concentrates on key works showing the complexity of localization and partial certainty of the functions of monoamine oxidase in the intestine, the features of changes in enzyme activity in ontogenesis and participation in the development of pathological conditions. The possibilities of using monoamine oxidase as a diagnostic marker or pharmacological target for the therapy of intestinal diseases are considered.