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Updated: Jun 26, 2026
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Local Application of Drugs to Study Nicotinic Acetylcholine Receptor Function in Mouse Brain Slices
Published on: October 29, 2012
Nicotine activates TRPM5-dependent and independent taste pathways
Albino J Oliveira-Maia1, Jennifer R Stapleton-Kotloski, Vijay Lyall
1Instituto de Histologia e Embriologia, Faculdade de Medicina and Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-319 Porto, Portugal.
Summary
Nicotine
Area of Science:
- Neuroscience
- Sensory Biology
- Pharmacology
Background:
- Nicotine's bitter taste is crucial for tobacco addiction.
- The specific taste pathways for nicotine remain largely unknown.
Purpose of the Study:
- Investigate nicotine's taste pathways using TRPM5 and nicotinic acetylcholine receptors (nAChRs).
- Determine if nicotine activates peripheral and central taste pathways.
Main Methods:
- Utilized Trpm5 knockout mice and wild-type littermates.
- Administered mecamylamine, a nAChR antagonist, to assess its effects.
- Recorded chorda tympani (CT) nerve responses and behavioral aversion.
- Analyzed gustatory cortex (GC) neural ensemble activity in rats.
Main Results:
- Trpm5 knockout mice showed reduced, but not eliminated, CT responses to nicotine.
- Mecamylamine inhibited nicotine-induced CT responses and aversion behaviors.
- Rats and their GC neural activity could discriminate between nicotine and quinine.
- Mecamylamine impaired behavioral and neural discrimination between these bitter tastants.
Conclusions:
- Nicotine activates TRPM5-dependent pathways, shared with other bitter tastants.
- Nicotine also engages nAChR-dependent and TRPM5-independent pathways.
- These distinct pathways create a unique sensory profile for nicotine, contributing to tobacco use.
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