Taste Memory Formation: Role of Nucleus Accumbens

Background: Learning and memory is basic aspects in neurogenetics as most of the neurological disorders start with dementia or memory loss. Several genes associated with memory formation have been discovered. MicroRNA genes miR-1000 and miR-375 were reported to be associated with neural integration and glucose homeostasis in some insects and vertebrates. However, neuronal function of these genes is yet to be established in D. melanogaster. Objective: Possible role of miR-1000 and miR-375 in learning and memory formation in this fly has been explored in the present study. Methods: Both appetitive and aversive olfactory conditional learning were tested in the miR-1000 and miR-375 knockout (KO) strains and compared with wild one. Five days old third instar larvae were trained by allowing them to be associated with an odor with reward (fructose) or punishment (salt). Then, the larvae were tested to calculate their preferences to the odor trained with. Learning index (LI) values and larval locomotion speed were calculated for all strains. Results: No significant difference was observed for larval locomotion speed in mutant strains. Knockout strain of miR-1000 showed significant deficiency in both appetitive and aversive memory formation whereas miR-375 KO strain showed a significantly lower response only in appetitive one. Conclusion: The results of the present study indicate important role played by these two genes in forming short-term memory in D. melanogaster.

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Neurometabolic alterations in the nucleus accumbens of smokers assessed with 1 H magnetic resonance spectroscopy: The role of glutamate and neuroinflammation

Addiction Biology ◽

10.1111/adb.13027 ◽

2021 ◽

Author(s):

Colette A. Steinegger ◽

Niklaus Zoelch ◽

Andreas Hock ◽

Anke Henning ◽

Etna J.E. Engeli ◽

...

Keyword(s):

Nucleus Accumbens ◽

Magnetic Resonance ◽

Magnetic Resonance Spectroscopy ◽

Resonance Spectroscopy

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The Role of Neuropeptide Y in the Nucleus Accumbens

International Journal of Molecular Sciences ◽

10.3390/ijms22147287 ◽

2021 ◽

Vol 22 (14) ◽

pp. 7287

Author(s):

Masaki Tanaka ◽

Shunji Yamada ◽

Yoshihisa Watanabe

Keyword(s):

Nervous System ◽

Nucleus Accumbens ◽

Neuropeptide Y ◽

Emotional Behavior ◽

Characteristic Functions ◽

Receptor Subtypes ◽

Neuroendocrine Mechanisms ◽

Fear And Anxiety ◽

The Brain

Neuropeptide Y (NPY), an abundant peptide in the central nervous system, is expressed in neurons of various regions throughout the brain. The physiological and behavioral effects of NPY are mainly mediated through Y1, Y2, and Y5 receptor subtypes, which are expressed in regions regulating food intake, fear and anxiety, learning and memory, depression, and posttraumatic stress. In particular, the nucleus accumbens (NAc) has one of the highest NPY concentrations in the brain. In this review, we summarize the role of NPY in the NAc. NPY is expressed principally in medium-sized aspiny neurons, and numerous NPY immunoreactive fibers are observed in the NAc. Alterations in NPY expression under certain conditions through intra-NAc injections of NPY or receptor agonists/antagonists revealed NPY to be involved in the characteristic functions of the NAc, such as alcohol intake and drug addiction. In addition, control of mesolimbic dopaminergic release via NPY receptors may take part in these functions. NPY in the NAc also participates in fat intake and emotional behavior. Accumbal NPY neurons and fibers may exert physiological and pathophysiological actions partly through neuroendocrine mechanisms and the autonomic nervous system.

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