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Functional Dissociation In Frontal And Striatal Areas For Processing Of Positive And Negative Reward Information, Xun Liu, David K. Powell, Hongbin Wang, Brian T. Gold, Christine R. Corbly, Jane E. Joseph

Neuroscience Faculty Publications

Reward-seeking behavior depends critically on processing of positive and negative information at various stages such as reward anticipation, outcome monitoring, and choice evaluation. Behavioral and neuropsychological evidence suggests that processing of positive (e.g., gain) and negative (e.g., loss) reward information may be dissociable and individually disrupted. However, it remains uncertain whether different stages of reward processing share certain neural circuitry in frontal and striatal areas, and whether distinct but interactive systems in these areas are recruited for positive and negative reward processing. To explore these issues, we used a monetary decision-making task to investigate the roles of frontal and striatal …

The Role Of Macrophages In Olfactory Neurogenesis, Aaron S. Borders

Theses and Dissertations--Physiology

Olfactory sensory neurons (OSNs) undergo continual degeneration and replacement throughout life, a cycle that can be synchronized experimentally by performing olfactory bulbectomy (OBX). OBX induces apoptosis of mature OSNs, which is followed by an increase in the proliferation of progenitor basal cells. Macrophages, functionally diverse immune effector cells, phagocytose the apoptotic OSNs and regulate the proliferation of basal cells. This provides an advantageous environment to study how macrophages regulate neuronal death, proliferation, and replacement.

The purpose of this dissertation was to identify the cellular and molecular mechanisms by which macrophages regulate the degeneration/proliferation cycle of OSNs. Macrophages were selectively depleted …

Functional Properties Of L-Glutamate Regulation In Anesthetized And Freely Moving Mice, Kevin N. Hascup

Theses and Dissertations--Neuroscience

L-glutamate (Glu) is the predominant excitatory neurotransmitter in the mammalian central nervous system with involvement encompassing learning and memory, cognition, plasticity, and motor movement. Dysregulation of the glutamatergic system is implicated in several neurological disorders including Parkinson’s disease, Alzheimer’s disease, Huntington’s disease and amyotrophic lateral sclerosis. The mechanisms underlying these neurological disorders are not clear, but evidence suggests that abnormal Glu neurotransmission plays a role. Elevated levels of Glu in the synaptic cleft overstimulate the N-methyl-Daspartate receptor leading to excitotoxicity, which causes neuronal loss in chronic neurological diseases. What is less understood is the source for the elevated Glu levels. …

Role Of Calcium And Nitric Oxide Synthase (Nos) In Brain Mitochondrial Dysfunction, Vidya Nag Nukala

Theses and Dissertations--Neuroscience

Mitochondria are essential for promoting cell survival and growth through aerobic metabolism and energy production. Mitochondrial function is typically analyzed using mitochondria freshly isolated from tissues and cells because they yield tightly coupled mitochondria, whereas those from frozen tissue can consist of broken mitochondria and membrane fragments. A method, utilizing a well-characterized cryoprotectant such as dimethyl sulfoxide (DMSO), is described. Such mitochondria show preserved structure and function that presents us with a possible strategy to considerably expand the time-frame and the range of biochemical, molecular and metabolic studies that can be performed without the constraints of mitochondrial longevity ex vivo …