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Chronic psychological stress affects gastrointestinal physiology which may underpin alterations in the immune response and epithelial transport, both functions are partly regulated by enteric nervous system. However, its effects on enteric neuroplasticity are still unclear. This study aims to investigate the effects of chronic unpredictable psychological stress on intestinal motility and prominent markers of enteric function.Adult male C57BL/6J mice were exposed to 19 day of unpredictable stress protocol schedule of social defeat and overcrowding. We investigated the effects on plasma corticosterone, food intake, and body weight. In vivo gastrointestinal motility was assessed by fecal pellet output and by whole-gastrointestinal transit (using the carmine red method). Tissue monoamine level, neural and glial markers, neurotrophic factors, monoamine signaling, and Toll-like receptor expression in the proximal and distal colon, and terminal ileum were also assessed.Following chronic unpredictable psychological stress, stressed mice showed increased food intake and body weight gain (Unpredictable psychological chronic stress induces region-specific impairment in monoamine levels and neuroplasticity markers that may relate to delayed intestinal transit.

This study is the first report of the development of monoclonal antibodies (MAbs) against gizzerosine (GZ), one of the causative agents of black vomit, a serious poultry disease. Balb/c mice were immunized with different GZ conjugates; the most immunogenic conjugate in experimental animals was determined by enzyme-linked immunoadsorbent assays (ELISA). Somatic fusions were carried out using splenic lymphocytes from GZ-immune mice and the NSO/2 myeloid cell line. Primary selection of hybridomas secreting antibodies to GZ was done using a direct ELISA, with GZ bound to bovine serum albumin (BSA), GZ directly bound to maleinimide preactivated plates and histamine bound to BSA, a GZ related biogenic amine present in fish meal. Four MAbs--3H4, 3H10, and 5B1 of the IgG1 isotype, and 8G7 of the Ig2a isotype-were specific to GZ and did not cross-react with histamine. Only monoclonals 3H4 and 8G7 bound GZ in solution by means of a competitive ELISA. Finally, to determine the performance of the competitive ELISA developed with the MAbs, experiments were conducted with GZ in solution (0 to 10 microg/ml) and with GZ labeled with horseradish peroxidase (HRP) as the tracer; the antibody complex was captured by using rabbit anti-mouse IgG preactivated ELISA plates. These experiments showed that monoclonal anti-GZ-3H4 generates a more sensitive assay close to linearity in the range about of 0.1 to 10 microg/ml of GZ. No cross-reaction was observed with histamine, histidine, or lysine at all concentrations tested.