α7-Nicotinic acetylcholine receptor: role in early odor learning preference in mice

• Published in: PloS one 2012-04, Vol.7 (4), p.e35251-e35251
• Main Authors: Hellier, Jennifer L, Arevalo, Nicole L, Smith, Lynelle, Xiong, Ka-Na, Restrepo, Diego
• Format: Article
• Language: English
• Subjects: Acetylcholine receptors (nicotinic); alpha7 Nicotinic Acetylcholine Receptor; Animals; Associative learning; Benzaldehydes; Biology; Brain research; Child psychology; Conditioning; Cyclohexenes; Developmental biology; Information processing; Laboratories; Learning; Learning - physiology; Medicine; Mice; Mice, Mutant Strains; Odorant receptors; Odorants; Odors; Olfactory bulb; Olfactory Bulb - metabolism; Olfactory discrimination learning; Preferences; Psychiatry; Psychopharmacology; Rats; Receptors; Receptors, Nicotinic - genetics; Receptors, Nicotinic - metabolism; Rodents; Schizophrenia; Sensory evaluation; Sensory integration; Smell - genetics; Smell - physiology; Studies; Terpenes; Traumatic brain injury
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0035251

Recently, we have shown that mice with decreased expression of α7-nicotinic acetylcholine receptors (α7) in the olfactory bulb were associated with a deficit in odor discrimination compared to wild-type mice. However, it is unknown if mice with decreased α7-receptor expression also show a deficit in early odor learning preference (ELP), an enhanced behavioral response to odors with attractive value observed in rats. In this study, we modified ELP methods performed in rats and implemented similar conditions in mice. From post-natal days 5-18, wild-type mice were stroked simultaneously with an odor presentation (conditioned odor) for 90 s daily. Control mice were only stroked, exposed to odor, or neither. On the day of testing (P21), mice that were stroked in concert with a conditioned odor significantly investigated the conditioned odor compared to a novel odor, as observed similarly in rats. However, mice with a decrease in α7-receptor expression that were stroked during a conditioned odor did not show a behavioral response to that odorant. These results suggest that decreased α7-receptor expression has a role in associative learning, olfactory preference, and/or sensory processing deficits.