title: Functional alterations in gut contractility after connexin36 ablation and evidence for gap junctions forming electrical synapses between nitrergic enteric neurons.
abstract: Neurons in the enteric nervous system utilize numerous neurotransmitters to orchestrate rhythmic gut smooth muscle contractions. We examined whether electrical synapses formed by gap junctions containing connexin36 also contribute to communication between enteric neurons in mouse colon. Spontaneous contractility properties and responses to electrical field stimulation and cholinergic agonist were altered in gut from connexin36 knockout vs. wild-type mice. Immunofluorescence revealed punctate labelling of connexin36 that was localized at appositions between somata of enteric neurons immunopositive for the enzyme nitric oxide synthase. There is indication for a possible functional role of gap junctions between inhibitory nitrergic enteric neurons.
authors.affiliation: Department of Physiology, Faculty of Medicine, University of Manitoba, Winnipeg, Canada.
authors.forename: James Imre
authors.initials: JI
authors.lastname: Nagy
authors.affiliation: Department of Physiology, Faculty of Medicine, University of Manitoba, Winnipeg, Canada; Department of Immunology and Internal Medicine section of Gastroenterology, Faculty of Medicine, University of Manitoba, Winnipeg, Canada.
authors.forename: Viridiana
authors.initials: V
authors.lastname: Urena-Ramirez
authors.affiliation: Department of Immunology and Internal Medicine section of Gastroenterology, Faculty of Medicine, University of Manitoba, Winnipeg, Canada. Electronic address: jeghia@med.umanitoba.ca.
authors.forename: Jean-Eric
authors.initials: JE
authors.lastname: Ghia
mesh_terms: D000818:Animals; D018679:Cholinergic Agonists / Q000494:pharmacology; D003106:Colon / Q000294:innervation / Q000502:physiology*; D017630:Connexins / Q000235:genetics / Q000378:metabolism*; D054351:Electrical Synapses / Q000378:metabolism* / Q000502:physiology; D017615:Enteric Nervous System / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D017353:Gene Deletion; D051379:Mice; D008810:Mice, Inbred C57BL; D009119:Muscle Contraction; D009130:Muscle, Smooth / Q000294:innervation / Q000502:physiology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D052250:Nitric Oxide Synthase Type III / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D000097004:Gap Junction delta-2 Protein
chemical_list: D018679:Cholinergic Agonists; D017630:Connexins; D052250:Nitric Oxide Synthase Type III; D000097004:Gap Junction delta-2 Protein
keywords: Connexin36 knockout; EGFP reporter; Gastrointestinal system; Immunofluorescence; Nitric oxide; Nitric oxide synthase