793 Neuronal Nitric Oxide Synthase (Nos1) Regulates Body Weight Following Chronic Dietary Restriction

Abstract

G A A b st ra ct s significant increase in baseline Isc following mucosal addition to the Ussing Chamber, and in the case of both strains this was attributed to a heat-resistant, secreted factor. Moreover, the Isc response elicited by L. salivarius UCC118 was influenced by the removal of chloride ions. Both probiotics significantly inhibited cholinergic-induced changes in ion transport, and both displayed sensitivity to pretreatment with the neurotoxin, tetrodotoxin (TTx); with approximately 60% of the L. salivarius UCC118 response sensitive to inhibition by TTx (P < 0.001). Consistent with this finding, neurally-stimulated Isc was significantly reduced in tissues collected from animals fed L. salivarius UCC118 for two weeks (P < 0.05). Both probiotics significantly decreased baseline Isc and B. infantis 35624 significantly increased tranepithelial resistance after in vivo administration. Both strains significantly reduced small intestinal transit (P < 0.05), while neither strain had an effect on fecal pellet output or fecal water content after two weeks feeding. Summary & Conclusion: These results highlight the divergent mechanisms by which specific probiotics may influence colonic secretomotor function in vitro and in vivo, with each probiotic inducing characteristically different physiological response on colonic ion transport. This study also emphasizes the utility of Ussing chambers as an in vitro tool to screen potential probiotic strains in an effort to predict in vivo responses. We would like to acknowledge Alimentary Health Ltd. for the provision of the probiotic strains used in this study