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Nicotine suppresses hyperexcitability of colonic sensory neurons and visceral hypersensivity in mouse model of colonic inflammation.

ABSTRACT: Recently, we reported that nicotine in vitro at a low 1-?M concentration suppresses hyperexcitability of colonic dorsal root ganglia (DRG; L(1)-L(2)) neurons in the dextran sodium sulfate (DSS)-induced mouse model of acute colonic inflammation (1). Here we show that multiple action potential firing in colonic DRG neurons persisted at least for 3 wk post-DSS administration while the inflammatory signs were diminished. Similar to that in DSS-induced acute colitis, bath-applied nicotine (1 ?M) gradually reduced regenerative multiple-spike action potentials in colonic DRG neurons to a single action potential in 3 wk post-DSS neurons. Nicotine (1 ?M) shifted the activation curve for tetrodotoxin (TTX)-resistant sodium currents in inflamed colonic DRG neurons (voltage of half-activation changed from -37 to -32 mV) but did not affect TTX-sensitive currents in control colonic DRG neurons. Further, subcutaneous nicotine administration (2 mg/kg b.i.d.) in DSS-treated C57Bl/J6 male mice resulted in suppression of hyperexcitability of colonic DRG (L(1)-L(2)) neurons and the number of abdominal constrictions in response to intraperitoneal injection of 0.6% acetic acid. Collectively, the data suggest that neuronal nicotinic acetylcholine receptor-mediated suppression of hyperexcitability of colonic DRG neurons attenuates reduction of visceral hypersensitivity in DSS mouse model of colonic inflammation.

SUBMITTER: Abdrakhmanova GR

PROVIDER: S-EPMC3330777 | biostudies-literature | 2012 Apr

REPOSITORIES: biostudies-literature

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Nicotine suppresses hyperexcitability of colonic sensory neurons and visceral hypersensivity in mouse model of colonic inflammation.

Abdrakhmanova Galya R GR Kang Minho M Imad Damaj M M Akbarali Hamid I HI

American journal of physiology. Gastrointestinal and liver physiology 20120112 7

Recently, we reported that nicotine in vitro at a low 1-μM concentration suppresses hyperexcitability of colonic dorsal root ganglia (DRG; L(1)-L(2)) neurons in the dextran sodium sulfate (DSS)-induced mouse model of acute colonic inflammation (1). Here we show that multiple action potential firing in colonic DRG neurons persisted at least for 3 wk post-DSS administration while the inflammatory signs were diminished. Similar to that in DSS-induced acute colitis, bath-applied nicotine (1 μM) grad ...[more]

PMID: 22241859

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Dataset Information

Nicotine suppresses hyperexcitability of colonic sensory neurons and visceral hypersensivity in mouse model of colonic inflammation.

Publications

Nicotine suppresses hyperexcitability of colonic sensory neurons and visceral hypersensivity in mouse model of colonic inflammation.

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