#The authors declare that there is no conflict of interest to disclose.
Lactobacillus reuteri enhances excitability of colonic AH neurons by inhibiting calcium-dependent potassium channel opening
Article first published online: 4 FEB 2009
© 2009 The Authors Journal compilation © 2009 Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd
Journal of Cellular and Molecular Medicine
Volume 13, Issue 8b, pages 2261–2270, August 2009
How to Cite
Kunze, W. A., Mao, Y.-K., Wang, B., Huizinga, J. D., Ma, X., Forsythe, P. and Bienenstock, J. (2009), Lactobacillus reuteri enhances excitability of colonic AH neurons by inhibiting calcium-dependent potassium channel opening. Journal of Cellular and Molecular Medicine, 13: 2261–2270. doi: 10.1111/j.1582-4934.2009.00686.x
- Issue published online: 26 NOV 2009
- Article first published online: 4 FEB 2009
- Received: July 17, 2008; Accepted: September 1, 2008
- ion channel;
- enteric nervous system;
- calcium-dependent potassium channel;
Probiotics are live non-pathogenic commensal organisms that exert therapeutic effects in travellers’ diarrhea, irritable bowel syndrome and inflammatory bowel disease. Little is known about mechanisms of action of commensal bacteria on intestinal motility and motility-induced pain. It has been proposed that probiotics affect intestinal nerve function, but direct evidence for this has thus far been lacking. We hypothesized that probiotic effects might be mediated by actions on colonic intrinsic sensory neurons. We first determined whether sensory neurons were present in rat colon by their responses to chemical mucosal stimulation and identified them in terms of physiological phenotype and soma morphotype. Enteric neuron excitability and ion channel activity were measured using patch clamp recordings. We fed 109Lactobacillus reuteri (LR) or vehicle control to rats for 9 days. LR ingestion increased excitability (threshold for evoking action potentials) and number of action potentials per depolarizing pulse, decreased calcium-dependent potassium channel (IKCa) opening and decreased the slow afterhyperpolarization (sAHP) in sensory AH neurons, similar to the IKCa antagonists Tram-34 and clotrimazole. LR did not affect threshold for action potential generation in S neurons. Our results demonstrate that LR targets an ion channel in enteric sensory nerves through which LR may affect gut motility and pain perception.