Molecular and Cellular PharmacologyIndividual variation in the expression profiles of nicotinic receptors in the olfactory bulb and trigeminal ganglion and identification of α2, α6, α9, and β3 transcripts
Section snippets
Animals and tissue collection
Naive adult Sprague–Dawley rats (200–400 g, Virus Antibody Free/Plus, Charles River Laboratories) were used in this study. The animals were housed individually in polycarbonate cages in a vivarium with controlled lighting (12 hr light/12 hr dark) and had ad lib. access to food and water. The temperature and relative humidity were maintained at 20–24° and 40–60%, respectively. Rats were anesthetized deeply with 70% CO2 and then decapitated. After the brain was removed from the skull, the OB and
Multiple neuronal nicotinic receptor subunit mRNAs are expressed in the OB and TG
Analysis of nAChR gene expression in the OB and TG showed individual variation and tissue-specific differences. In the OB, all animals expressed α2, α3, α4, α5, α7, β2, and β4 mRNAs in comparison with 17, 28, and 33% of the animals expressing α6, β3, and α9 mRNAs, respectively. More specifically, one male and two female rats expressed detectable levels of α6 mRNA. The same male rat also expressed a low level of α9 mRNA [see Fig. 1 (top panel) and Table 2].
Several variations in nAChR expression
Discussion
The new information we report here shows that nAChR gene expression varies among individual rats as well as from the OB to the TG. To our knowledge, no study of this nature has been done in sensory tissue of the rat or human despite the general importance of normative tissue differences as well as the need to better understand why some individuals have a greater degree of chemosensitivity to endogenous ACh or nicotine from tobacco products. Although the range for individual chemosensory
Acknowledgements
We thank Sheri Bowman and Walden Hearn for excellent technical assistance and Elyse Jung for DNA sequencing assistance. This project was supported by the UNC-RJR Collaborative Olfactory Research Program.
References (51)
- et al.
Neuronal nicotinic acetylcholine receptors expressed in Xenopus oocytes have a pentameric quaternary structure
J Biol Chem
(1991) - et al.
Chemosensory event-related potentials in manRelation to olfactory and painful sensations elicited by nicotine
Electroencephalogr Clin Neurophysiol
(1992) - et al.
Presence of α-bungarotoxin-sensitive nicotinic acetylcholine receptors in rat olfactory bulb neurons
Neurosci Lett
(1994) - et al.
Comparative laminar distribution of various autoradiographic cholinergic markers in adult rat main olfactory bulb
J Chem Neuroanat
(1995) - et al.
Cholinergic modulation of excitability in the rat olfactory bulbEffect of local application of cholinergic agents on evoked field potentials
Neuroscience
(1991) - et al.
Identification of acetylcholine receptors in adult rat trigeminal ganglion neurons
Brain Res
(1993) - et al.
Presence of both odor identification and detection deficits in Alzheimer’s disease
Brain Res Bull
(1987) - et al.
Olfactory thresholds are associated with degree of dementia in Alzheimer’s disease
Neurobiol Aging
(1990) - et al.
Olfactory-related changes in Alzheimer’s diseaseA quantitative neuropathologic study
Brain Res Bull
(1993) - et al.
Olfactory bulb lesions in Alzheimer’s disease
Neurobiol Aging
(1992)
Characteristics of memory dysfunction in olfactory bulbectomized rats and the effects of cholinergic drugs
Behav Brain Res
Individual differences in cardiac and EMG activity after smoking
Pers Individ Differ
Distribution of α-bungarotoxin binding sites in the central nervous system and peripheral organs of the rat
Toxicon
Nicotinic receptors in sensory ganglia
Brain Res
α9An acetylcholine receptor with novel pharmacological properties expressed in rat cochlear hair cells
Cell
Characterization of the nicotinic acetylcholine receptor β3 gene. Its regulation within the avian nervous system is effected by a promoter 143 base pairs in length
J Biol Chem
Identification of the subunits of the nicotinic cholinergic receptors in the rat cochlea using RT-PCR and in situ hybridization
Mol Brain Res
β3A new member of nicotinic acetylcholine receptor gene family is expressed in brain
J Biol Chem
Pentameric structure and subunit stoichiometry of a neuronal nicotinic acetylcholine receptor
Nature
Neuronal nicotinic acetylcholine receptors
Olfactory and trigeminal responses to nicotine
Drug Dev Res
Enantiomeric purity of nicotine in tobacco smoke condensate
Med Sci Res
Olfactory discrimination of nicotine-enantiomers by smokers and non-smokers
Chem Senses
Diversity of nicotinic acetylcholine receptors in rat brain. V. α-Bungarotoxin-sensitive nicotinic receptors in olfactory bulb neurons and presynaptic modulation of glutamate release
J Pharmacol Exp Ther
Neuronal nicotinic receptor expression in sensory neurons of the rat trigeminal ganglionDemonstration of α3β4, a novel subtype in the mammalian nervous system
J Neurosci
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2008, Respiratory Physiology and Neurobiology5-Hydroxytryptamine directly inhibits neuronal nicotinic acetylcholine receptors in rat trigeminal ganglion neurons
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Present address of Dr. James C. Walker: FSU-Sensory Research Institute, 1800 E. Paul Dr., Tallahassee, FL 32306-2741.