title: Degranulation of mast cells due to compound 48/80 induces concentration-dependent intestinal contraction in rainbow trout (Oncorhynchus mykiss Walbaum) ex vivo.
abstract: Rainbow trout (Oncorhynchus mykiss) intestinal strips (n = 10) were mounted in an isolated organ bath and the effect of incremental doses of compound 48/80 was recorded. Compound 48/80 induced concentration-related contraction in all the examined strips following a sigmoidal dose-response curve fit. Values for maximal contraction (E(max) , g cm(-2)), negative logarithm of the EC(50) (pD(2)), and hill slope were, respectively (mean±standard error), 12.88 ± 0.51, 1.88 ± 0.05, 1.49 ± 0.27. The histological modification induced on mast cells (MCs) due to compound 48/80 was characterized by mean of gray-levels and texture analysis. Significant differences were observed between gray-levels values (Linear mixed model, P<0.01), contrast, and entropy (Linear mixed model, P<0.05) of MCs from compound 48/80-treated strips compared with MCs from untreated strips. Moreover, maximal intestinal contraction (due to compound 48/80) correlates positively and significantly (Pearson and Spearman correlations, P<0.05) with degranulation intensity determined by means of gray-levels analysis. Four antisera were tested on intestinal sections and no MCs positive to serotonin, substance P, met-enkephalin, and bombesin were found. This study demonstrates that compound 48/80 induces the degranulation of trout intestinal MCs ex vivo, and that the aforementioned degranulation promotes a concentration-dependent intestinal contraction.
authors.affiliation: Department of Food Science, University of Teramo, Teramo, Italy. mmanera@unite.it
authors.forename: M
authors.initials: M
authors.lastname: Manera
authors.forename: A
authors.initials: A
authors.lastname: Giammarino
authors.forename: C
authors.initials: C
authors.lastname: Borreca
authors.forename: L
authors.initials: L
authors.lastname: Giari
authors.forename: B S
authors.initials: BS
authors.lastname: Dezfuli
mesh_terms: D000818:Animals; D015550:Cell Degranulation; D007422:Intestines / Q000187:drug effects / Q000502:physiology; D008407:Mast Cells / Q000187:drug effects / Q000502:physiology*; D009119:Muscle Contraction / Q000187:drug effects; D017686:Oncorhynchus mykiss / Q000502:physiology*; D003189:p-Methoxy-N-methylphenethylamine / Q000494:pharmacology*
chemical_list: D003189:p-Methoxy-N-methylphenethylamine