The Behavioral Significance of Nitric Oxide in a Primary Olfactory Network: Insights into Learning and Memory in the Antennal Lobe of Manduca Sexta

Persistent Link:
http://hdl.handle.net/10150/306943
Title:
The Behavioral Significance of Nitric Oxide in a Primary Olfactory Network: Insights into Learning and Memory in the Antennal Lobe of Manduca Sexta
Author:
Gage, Stephanie Lauren
Issue Date:
2013
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Nitric oxide (NO) is a gaseous, unconventional chemical messenger suggested to play a fundamental role in olfaction. This thesis focuses on the role of NO in a primary olfactory center, the antennal lobe (AL) of the moth, Manduca sexta (M. sexta), to understand how NO affects olfactory-guided behavior. Studies in M. sexta report that NO is produced upon odor stimulation and has profound effects at the physiological level, but little is known about its significance to behavior. The central hypothesis examined in this thesis is that NO functions as a neuromodulator of olfactory-guided behavior in a circadian fashion. This hypothesis is examined in the following three studies: The first study questions whether basal levels of NO fluctuate with the light cycle. M. sexta are nocturnal animals that actively engage in odor-seeking behaviors at night. Using an NO sensor, NO concentrations were measured in the AL, optic lobe, and the remainder of the brain during subjective day and subjective night. NO concentrations are higher in the AL and optic lobes at night, suggesting that NO is likely involved in olfactory-guided behavior. The second inquiry focuses on developing a technique to manipulate NO levels in the AL and whether a specific behavior is affected. Using the proboscis extension reflex, olfactory conditioning is used to ask three questions: (1) does NO affect odor detection, (2) does NO affect discrimination between odorants, and (3) does NO affect learning and memory? Results indicate that NO affects short-term memory but does not affect odor detection, or discrimination between dissimilar odorants. The third inquiry examines the role of NO in memory and circadian time. It asks: (1) is there an optimal time of day for learning and memory, and (2) does the role of NO in memory change depending on the time of olfactory conditioning? Results indicate that NO in memory is modulated by circadian time. Taken together, these results suggest a unique functional role for NO in olfactory-guided behavior with two main conclusions: (1) NO modulates short-term memory in the AL, and (2) NO may be important for the circadian regulation of memory.
Type:
text; Electronic Dissertation
Keywords:
moth; olfaction; Neuroscience; circadian
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Neuroscience
Degree Grantor:
University of Arizona
Advisor:
Nighorn, Alan

Full metadata record

DC FieldValue Language
dc.language.isoen_USen_US
dc.titleThe Behavioral Significance of Nitric Oxide in a Primary Olfactory Network: Insights into Learning and Memory in the Antennal Lobe of Manduca Sextaen_US
dc.creatorGage, Stephanie Laurenen_US
dc.contributor.authorGage, Stephanie Laurenen_US
dc.date.issued2013-
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractNitric oxide (NO) is a gaseous, unconventional chemical messenger suggested to play a fundamental role in olfaction. This thesis focuses on the role of NO in a primary olfactory center, the antennal lobe (AL) of the moth, Manduca sexta (M. sexta), to understand how NO affects olfactory-guided behavior. Studies in M. sexta report that NO is produced upon odor stimulation and has profound effects at the physiological level, but little is known about its significance to behavior. The central hypothesis examined in this thesis is that NO functions as a neuromodulator of olfactory-guided behavior in a circadian fashion. This hypothesis is examined in the following three studies: The first study questions whether basal levels of NO fluctuate with the light cycle. M. sexta are nocturnal animals that actively engage in odor-seeking behaviors at night. Using an NO sensor, NO concentrations were measured in the AL, optic lobe, and the remainder of the brain during subjective day and subjective night. NO concentrations are higher in the AL and optic lobes at night, suggesting that NO is likely involved in olfactory-guided behavior. The second inquiry focuses on developing a technique to manipulate NO levels in the AL and whether a specific behavior is affected. Using the proboscis extension reflex, olfactory conditioning is used to ask three questions: (1) does NO affect odor detection, (2) does NO affect discrimination between odorants, and (3) does NO affect learning and memory? Results indicate that NO affects short-term memory but does not affect odor detection, or discrimination between dissimilar odorants. The third inquiry examines the role of NO in memory and circadian time. It asks: (1) is there an optimal time of day for learning and memory, and (2) does the role of NO in memory change depending on the time of olfactory conditioning? Results indicate that NO in memory is modulated by circadian time. Taken together, these results suggest a unique functional role for NO in olfactory-guided behavior with two main conclusions: (1) NO modulates short-term memory in the AL, and (2) NO may be important for the circadian regulation of memory.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjectmothen_US
dc.subjectolfactionen_US
dc.subjectNeuroscienceen_US
dc.subjectcircadianen_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineNeuroscienceen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorNighorn, Alanen_US
dc.contributor.committeememberNighorn, Alanen_US
dc.contributor.committeememberDussor, Gregoryen_US
dc.contributor.committeememberOland, Lynneen_US
dc.contributor.committeememberPapaj, Danielen_US
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