BACKGROUND/ PURPOSE: Ncx (Enx, Hox11L.1)-deficient (Ncx-/-) mice develop mega-ileo-ceco-colon with a larger number of neuronal cells in the enteric ganglia. We investigated mechanisms related to this abnormality and directed our attention to the effects on gastrointestinal tract functions. METHODS: The number of NADPH diaphorase or cuprolinic blue-positive neuronal cells in the enteric ganglia was examined during growth of the mice. Neuronal cell death of enteric ganglia was assayed by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling. Function of the gastrointestinal tract was determined by measuring excretion time of the barium chloride given into the stomach. RESULTS: The number of neuronal cells decreased in control mice older than 2 weeks, and neuronal cell death was evident in the ganglia. However, the number of neuronal cells did not decrease in Ncx-/- mice, and cell death was rare. Excretion time of barium chloride was prolonged in all Ncx-/- mice examined and was improved by the administration of an inhibitor of nitric oxide synthase. CONCLUSIONS: Ncx participates in cell death of enteric neurons. Motor abnormality of the gastrointestinal tract in Ncx-/- mice may be attributed to the large number of neuronal cells.
BACKGROUND/ PURPOSE:Ncx (Enx, Hox11L.1)-deficient (Ncx-/-) mice develop mega-ileo-ceco-colon with a larger number of neuronal cells in the enteric ganglia. We investigated mechanisms related to this abnormality and directed our attention to the effects on gastrointestinal tract functions. METHODS: The number of NADPH diaphorase or cuprolinic blue-positive neuronal cells in the enteric ganglia was examined during growth of the mice. Neuronal cell death of enteric ganglia was assayed by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling. Function of the gastrointestinal tract was determined by measuring excretion time of the barium chloride given into the stomach. RESULTS: The number of neuronal cells decreased in control mice older than 2 weeks, and neuronal cell death was evident in the ganglia. However, the number of neuronal cells did not decrease in Ncx-/- mice, and cell death was rare. Excretion time of barium chloride was prolonged in all Ncx-/- mice examined and was improved by the administration of an inhibitor of nitric oxide synthase. CONCLUSIONS:Ncx participates in cell death of enteric neurons. Motor abnormality of the gastrointestinal tract in Ncx-/- mice may be attributed to the large number of neuronal cells.
Authors: J E Medland; C S Pohl; L L Edwards; S Frandsen; K Bagley; Y Li; A J Moeser Journal: Neurogastroenterol Motil Date: 2016-05-02 Impact factor: 3.598