The gut microbiome restores intrinsic and extrinsic nerve function in germ-free mice accompanied by changes in calbindin.
Neurogastroenterol Motil
; 27(5): 627-36, 2015 May.
Article
en En
| MEDLINE
| ID: mdl-25727007
ABSTRACT
BACKGROUND:
The microbiome is essential for normal myenteric intrinsic primary afferent neuron (IPAN) excitability. These neurons control gut motility and modulate gut-brain signaling by exciting extrinsic afferent fibers innervating the enteric nervous system via an IPAN to extrinsic fiber sensory synapse. We investigated effects of germ-free (GF) status and conventionalization on extrinsic sensory fiber discharge in the mesenteric nerve bundle and IPAN electrophysiology, and compared these findings with those from specific pathogen-free (SPF) mice. As we have previously shown that the IPAN calcium-dependent slow afterhyperpolarization (sAHP) is enhanced in GF mice, we also examined the expression of the calcium-binding protein calbindin in these neurons in these different animal groups.METHODS:
IPAN sAHP and mesenteric nerve multiunit discharge were recorded using ex vivo jejunal gut segments from SPF, GF, or conventionalized (CONV) mice. IPANs were excited by adding 5 µM TRAM-34 to the serosal superfusate. We probed for calbindin expression using immunohistochemical techniques. KEYRESULTS:
SPF mice had a 21% increase in mesenteric nerve multiunit firing rate and CONV mice a 41% increase when IPANs were excited by TRAM-34. For GF mice, this increase was barely detectable (2%). TRAM-34 changed sAHP area under the curve by -77 for SPF, +3 for GF, or -54% for CONV animals. Calbindin-immunopositive neurons per myenteric ganglion were 36% in SPF, 24% in GF, and 52% in CONV animals. CONCLUSIONS & INFERENCES The intact microbiome is essential for normal intrinsic and extrinsic nerve function and gut-brain signaling.Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Potenciales de Acción
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Calbindinas
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Microbioma Gastrointestinal
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Vida Libre de Gérmenes
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Yeyuno
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Plexo Mientérico
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Neuronas Aferentes
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Año:
2015
Tipo del documento:
Article