Neuroscience and Neurobiology Commons^™

Target Validation And Pharmacological Characterization Of Novel Nmdar Modulators, Kiran Sapkota

Theses & Dissertations

The N-methyl-D aspartate receptors (NMDARs) are ligand-gated ion channels, which play important roles in learning and memory. Excessive activity of NMDARs is implicated in damage due to stroke and neurodegenerative diseases, whereas hypoactivity of NMDARs contributes to schizophrenia. The initial goal of my dissertation is to evaluate the potential role of the GluN2D-containing NMDARs in neuropathological, behavioral and cognitive alterations associated with schizophrenia and characterize the pharmacology and mechanisms of action of NMDAR modulators which could potentially be used to modulate these receptors in schizophrenia.

A subanesthetic dose of the NMDAR antagonist ketamine elicits symptoms of schizophrenia. This property led …

Dopamine Effects Of Stimulant And Non-Stimulant Drugs Used In The Treatment Of Attention Deficit Hyperactivity Disorder, Preeti Chalwadi

Theses and Dissertations

Attention deficit hyperactivity disorder (ADHD) is thought to be associated with dysfunction of ascending catecholamine neuronal systems, particularly dopamine (DA) and norepinephrine (NE). Dysfunction of these catecholamine neurons innervating the prefrontal cortex is hypothesized to underlie impaired executive functions. Dysfunction of the DA neurons innervating the striatum is additionally hypothesized to underlie deficits in motivation and reinforcement learning. However, mechanisms of action of therapeutic drugs used for treating ADHD have mainly focused on catecholamines in the prefrontal cortex and have not adequately addressed the role played by DA signaling in the striatum. Stimulants such as Adderall® and Ritalin® are chemically …

Design Of Novel Ion Channel Modulators, Vladimir Yarov-Yarovoy

Science Seminar Series

Function and modulation of neuronal sodium channels are critical for the neuromodulation of electrical excitability and synaptic transmission in neurons - the basis for many aspects of signal transduction, learning, memory and physiological regulation. Mutations in neuronal voltage-gated sodium channel genes are responsible for various human neurological disorders. Furthermore, human neuronal voltage-gated sodium channels are primary targets of therapeutic drugs used as local anesthetics and for treatment of neurological and cardiac disorders. Yarov-Yarovoy's lab is working on rational design of novel therapeutically useful blockers of voltage-gated sodium channels for treatment of pain and epilepsy. Serious, chronic pain affects at least …

Corticotropin Releasing Factor Receptor Type 1 Signaling In Epilepsy And Traumatic Brain Injury, V V Chakravarthi Narla

Electronic Thesis and Dissertation Repository

Stress increases the frequency by which epileptic seizures occur. Corticotropin-releasing factor (CRF) coordinates neuroendocrine, autonomic and behavioral response to stress. This thesis sought to study the cellular and molecular mechanisms by which CRF regulates the activity of neural circuits in the piriform cortex (PC) in normal and epileptic states. The PC is richly innervated by CRF and 5-HT containing axons arising from the central amygdala and raphe nucleus. CRFR₁ and 5-HT_2A/CRs have been shown to interact in a manner where CRFR activation subsequently potentiates the activity of 5-HT_2A/CRs. The first purpose of this thesis was …

Structural Dichotomy Of The Mind; The Role Of Sexual Neuromodulators, Ion G. Motofei, David L. Rowland

Journal of Mind and Medical Sciences

The mind (mental function) and sexuality represent two distinct environmental functions, but which are supported within the brain by a common (somatic-autonomic) neurobiological substrate. As a consequence, mental function takes on autonomic characteristics from the sexual-autonomic system (like autonomy, duality), while sexual function takes on features from mental functioning (such as lateralization). In this paper we discuss the lateralized action of two classes of sexual neuromodulators: hormones and pheromones. This process of lateralization is assimilated with the structural dichotomy of the mind.

A relatively similar process but related to informational dichotomy of the mind will be presented in a forthcoming …

Role Of Anterior Cingulate Cortex In Saccade Control, Sahand Babapoor-Farrokhran

Electronic Thesis and Dissertation Repository

Cognitive control is referred to the guidance of behavior based on internal goals rather than external stimuli. It has been postulated that prefrontal cortex is mainly involved in higher order cognitive functions. Specifically, anterior cingulate cortex (ACC), which is part of the prefrontal cortex, is suggested to be involved in performance monitoring and conflict monitoring that are considered to be cognitive control functions.

Saccades are the fast eye movements that align the fovea on the objects of interest in the environment. In this thesis, I have explored the role of ACC in control of saccadic eye movements. First, I performed …

The Neuroprotective Effects Of Endurance Training On The Aging Brain, Katelyn Norton

Electronic Thesis and Dissertation Repository

Dysregulation of autonomic control often develops with advancing age, favoring a chronic state of heightened sympathetic outflow with parasympathetic withdrawal. However, the mechanisms of this age-related autonomic impairment are not known and may relate to alterations in brain structure (e.g. cortical atrophy) and/or altered neural function, particularly in regions related to the cortical autonomic network, namely, the medial prefrontal cortex (MPFC), insula cortex (IC), and hippocampus (HC). Exercise exerts beneficial effects on brain structure and, in the case of cognition, neurologic function; however, how exercise affects regions of the brain related to autonomic function are not known. This thesis tested …

Cal And Magi Pdz Protein Regulation Of Crfr1 And 5-Ht2ar Trafficking And Signaling, Maha Mahmoud Hammad

Electronic Thesis and Dissertation Repository

PDZ (PSD95/Disc Large/Zona Occludens) domain-containing proteins are scaffolding proteins that play important roles in regulating the activity of G protein-coupled receptors. Corticotropin Releasing Factor Receptor 1 (CRFR1) and Serotonin 2A Receptor (5-HT_2AR) are two GPCRs that are commonly associated with mental disorders. Both receptors also contain a class I PDZ-binding motif at the carboxyl terminal tail. In the first chapter, we investigate the effects of CAL (CFTR-associated ligand) on regulating the trafficking and signaling of CRFR1. We demonstrate a role for CAL in inhibiting CRFR1 endocytosis, cell surface expression, and CRF-mediated ERK1/2 signaling via the CRFR1 PDZ-binding motif. …

Exploring The Relationship Between Behaviour And Neurochemistry In The Polyphenic Spider, Anelosimus Studiosus (Araneae: Theridiidae), Jennifer B. Price

Electronic Theses and Dissertations

The importance of social behaviour is evident in human society, but there are both costs and benefits associated with cooperation and sociality throughout the animal kingdom. At what point do the benefits outweigh the costs, and when do selective pressures favour sociality and colonization over solitude and independence? To investigate these questions, we have focused on an anomalous species of spider, Anelosimus studiosus, also known now as the northern social spider. Throughout its broad range, A. studiosus is solitary and aggressive, but recently, colonies of cooperative and social individuals have been observed at northern latitudes. This leads to two …

Diffuse Traumatic Brain Injury Induces Prolonged Immune Sysregulation And Potentiates Hyperalgesia Following A Peripheral Immune Challenge, Rachel K. Rowe, Gavin I. Ellis, Jordan L. Harrison, Adam D. Bachstetter, Gregory F. Corder, Linda J. Van Eldik, Bradley K. Taylor, Francesc Marti, Jonathan Lifshitz

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Background: Nociceptive and neuropathic pain occurs as part of the disease process after traumatic brain injury (TBI) in humans. Central and peripheral inflammation, a major secondary injury process initiated by the traumatic brain injury event, has been implicated in the potentiation of peripheral nociceptive pain. We hypothesized that the inflammatory response to diffuse traumatic brain injury potentiates persistent pain through prolonged immune dysregulation.

Results: To test this, adult, male C57BL/6 mice were subjected to midline fluid percussion brain injury or to sham procedure. One cohort of mice was analyzed for inflammation-related cytokine levels in cortical biopsies and serum along an …

Exploring The Effect Of Novel Small Molecules On Oligodendrocyte Precursor Proliferation, Sagune Sakya

University Scholar Projects

Gliomas, a type of brain tumor, can be difficult to treat and have a poor survival rate. One pathway that leads to glioma formation is excessive signaling by platelet derived growth factors (PDGF) through PDGF receptor α (PDGFRα). Through this research, I found that novel compounds that downregulate PDGFRα decrease proliferation of Oli-neu cells, an oligodendrocyte precursor cell model, and identified signaling pathways through which these compounds may exert their effect. Further investigation may identify targets for development of glioma treatments.

Development Of Vip-Sst Interneuron Associations In Mouse Neocortex And Entorhinal Cortex, Aayushi A. Mehta

Honors Scholar Theses

Cortical networks depend upon inhibition through the neurotransmitter GABA to control and coordinate specific spatiotemporal circuit patterns, underlying the exquisite complexity of neural signaling. Disinhibition, a form of inhibition where inhibitory neurons inhibit other inhibitory cells, further aids in amplifying local neural processing in a selective, organized manner. A subset of GABAergic interneurons, vasoactive intestinal peptide-expressing (VIP) cells, preferentially inhibit somatostatin interneurons, which provide inhibitory input onto pyramidal cells, thus creating an archetypal circuit illustrating disinhibition in the cortex. The aim of this anatomical study was to investigate variations in GABAergic VIP synapses onto somatostatin-expressing inhibitory interneurons in mice at …

The Influence Of Canine Aggression And Behavioral Treatment On Heart Rate Variability, Lydia Craig

Psychology Honors Projects

Dog aggression affects many, with nearly 5 million dog bites reported yearly in the United States alone. With the physical, emotional, and monetary costs of bites, it is of considerable interest to identify dogs that are likely to bite. One physiological measure that might serve as an index of aggression is heart rate variability (HRV), which refers to vagally mediated beat-to-beat change in heart rate. Low HRV has been associated with impaired emotional and behavioral regulation and stress in both humans and animals. To assess whether this measure corresponds with aggression in dogs, resting HRV was measured for dogs with …

Examination Of A Post-Stroke Drug Treatment For Its Effect On Blood Brain Barrier Permeability, And Gene Expression Changes In The Peri-Infarct Region, Ankita Anil Patel

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In this current study, we have investigated this a combination of fluoxetine, simvastatin and ascorbic acid administered daily beginning at 20-26 hours after stroke induction. We hope to understand therapeutic abilities by studying its effectiveness on the blood brain barrier permeability and gene expression changes of the microglial subtypes involved in neuro-inflammation and neurogenesis factors in the peri-infarct region. Our results indicate that S-enantiomer of fluoxetine may be more beneficial compared to the R-enantiomer. The S-enantiomer was effective in tightening the blood brain barrier in contrast to the R-enantiomer, in which the latter showed a greater Evans Blue dye permeability …

Fighting Forms Of Expression, Paul J.B. Hart

Animal Sentience

Even though Key (2016) has done a very thorough job of assembling evidence showing that fish are unlikely to have the neurological capacity to be conscious and feel pain, there will still be a significant number of behavioural biologists who want to continue maintaining that fish do have consciousness and suffer from pain. In this commentary the reasons for people resisting the conclusions of the evidence are discussed. The reasons revolve around three aspects of the debate: the overblown respect humans have for the powers of consciousness in our day-to-day behaviour, the often used assumption that the possession of complex …

High Affinity Block Of Icl,Swell By Thiol-Reactive Small Molecules, Sung H. Park

Theses and Dissertations

Ebselen (Ebs) is considered as a glutathione peroxidase (GPx) mimetic and primarily thought to function by scavenging intracellular reactive oxygen species (ROS). Previous to our work, Deng et al. (2010a) demonstrated complete block of I_Cl,swell with 15 microM Ebs following endothelin-1 (ET-1) induced activation of the current in cardiomyocytes. This block was presumed to take effect mainly via the quenching of ROS. Nonetheless, our work with DI TNC1 astrocytes strongly emphasizes that Ebs might function by an alternative mechanism based on its kinetic profile in blocking I_Cl,swell. Our experiments showed that 45 nM Ebs can fully block …

Anthropomorphic Denial Of Fish Pain, Lynne U. Sneddon, Matthew C. Leach

Animal Sentience

Key (2016) affirms that we do not know how the fish brain processes pain but denies — because fish lack a human-like cortex — that fish can feel pain. He affirms that birds, like fish, have a singly-laminated cortex and that the structure of the bird brain is quite different from that of the human brain, yet he does not deny that birds can feel pain. In this commentary we describe how Key cites studies that substantiate mammalian pain but discounts the same kind of data as evidence of fish pain. We suggest that Key's interpretations are illogical, do not …

Chronic Pancreatitis, Pain, And Anxiety In An Alcohol And High Fat Mouse Model, Tiffanie Clinkinbeard

Theses and Dissertations--Gerontology

Homeodynamic space (HDS) shrinks as vulnerability increases with aging and repeated damage to the cells. HDS is lost in alcoholic pancreatitis patients due to overconsumption of alcohol, smoking, and high fat diets. Etiologically relevant animal models for study of chronic pancreatitis (CP) are needed. In order to begin filling this gap a central purpose of this dissertation research was to examine relationships between the alcohol and high fat diet (AHF) and pancreatitis with attention to hypersensitivity and anxiety-like behaviors. The AHF diet induced pancreatitis described here etiologically mimics human risk factors of AHF consumption for advancement to alcoholic CP.

In …

Changes In Brain Water Content In The Rainbow Trout (Oncorhynchus Mykiss) And In The Goldfish (Carassius Auratus) Due To High External Ammonia Exposure, Phillip Q.H. Pham-Ho

Theses and Dissertations (Comprehensive)

In fishes, hyperammonemia may occur following feeding or exposure to abnormally high concentrations of environmental ammonia due to sewage effluents, agricultural run-off and in crowded aquaculture pens. Increased internal ammonia can result in hyperactivity, convulsions, coma and death. In mammals, it is also associated with potentially fatal brain edema, in which the accumulation of intracellular water results in swelling, increased intracranical pressure and herniation leading to death. Recently it was shown that rainbow trout (Oncorhynchus mykiss) and goldfish (Carassius auratus) experience brain swelling following exposure to high external ammonia (HEA). However, the mechanism of ammonia-induced brain …

Effect Of Prior Trauma Exposure On Alpha Amplitude, Heart Rate, And Self-Reported Negative Affect, Gina L. Denoble

All Master's Theses

This study was conducted to investigate whether the number of traumatic events an individual has previously experienced influences that individual’s physiological and psychological reactions when exposed to a negative affective stimulus followed by a mindfulness-based stress reduction (MBSR) intervention. Twenty-eight participants were placed into intact quasi-experimental groups based on their scores on the Traumatic Life Events Questionnaire (TLEQ). The negative affective stimulus consisted of a series of photos bearing negative affective valence. The photos were selected from the International Affective Picture System (IAPS), and paralleled the areas of trauma exposure evaluated by the TLEQ. All participants were exposed to the …

The Use Of Doublecortin To Quantify The Effects Of Pharmacological Treatment On Neurogenesis And Functional Recovery After Stroke, Amber Lee Hensley

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Ischemic strokes account for 87% of all strokes and can have debilitating effects on language, sensory, and motor skills. Currently, tPA is the only medication approved by the FDA for the treatment of ischemic stroke, but the window of time to administer the drug is very small. In this thesis, we investigate the use of a simvastatin and fluoxetine drug combination (FS) as a possible treatment for ischemic stroke victims. To analyze the effects of FS on neurogenesis and functional recovery, we utilize the Montoya Staircase and quantify the amount of neurogenesis using doublecortin. Although the results of this study …

Cross Sensitization Of Depressive-Like Behavior Through Two Depression Related Paradigms: Maternal Separation And Its Effect On The Forced Swim Test In The Guinea Pig, Amanda Danielle Schreibeis

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Separation and Its Effect on the Forced Swim Test In the Guinea Pig Early-life stress such as parental neglect, absence, or abandonment, has been hypothesized to increase the susceptibility for developing depression later in life via sensitization of stress-responsive physiological systems (e.g., pro-inflammatory cytokines, hypothalamic-pituitary-adrenal axis). Guinea pigs offer a potential model, but study has been limited to behavioral observations obtained during maternal separation tests. This thesis examined the generalization of this response by asking whether it would cross-sensitize to behavior in another depressive-related paradigm, the forced swim test. In three experiments, pups underwent three forced swim trials, in shallower …

Sk Channel Clustering In Sod1-G93a Motoneurons, Saihari Shekar Dukkipati

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Amyotrophic lateral sclerosis (ALS) is a devastating neuromuscular disease that currently has no cure and extremely limited treatment options. The specific mechanisms that underlie motoneuron degeneration and death, which are classical features of this disease, are mostly unknown. This thesis tests the hypothesis that small-conductance calcium-activated potassium channels (SK) may be downregulated in ALS motoneurons, as suggested by computational modelling. SK channel expression was measured in spinal alpha-motoneuron cell bodies or somata of wildtype (WT) and mutant (mt) SOD1-G93A mice, a transgenic animal model of ALS. Quantitative immunohistochemical analysis of the developmental expression of SK channel isoforms SK2 and SK3 …

The Role Of Oxidative Stress In The Mechanisms Of Ammonia-Induced Brain Swelling And Tolerance In The Goldfish (Carassius Auratus), David F. Jones Lisser Mr.

Theses and Dissertations (Comprehensive)

Toxic build-ups of ammonia can cause potentially fatal brain swelling in mammals, but such swelling is reversible in the anoxia- and ammonia-tolerant goldfish (Carassius auratus). The mechanisms of ammonia-induced brain swelling and tolerance remain elusive, but several studies have suggested a role for reactive oxygen species (ROS), which may damage proteins and lipids in the plasma membrane of astrocytes in the brain. As a result, osmotic gradients across cell membranes may be altered leading to water uptake by astrocytes and swelling. While a role for ROS has been proposed in mammals, no studies have addressed this question in …

Intrinsic And Extrinsic Regulation Of Pineal Melatonin Rhythms, Ye Li

Theses and Dissertations--Biology

Circadian rhythm is a biological rhythm with period of about 24 hours. Circadian rhythm is universal in phyla from bacteria to mammals and exists in different level from gene expression to behavior. Circadian system consists of three components: 1) a self-sustained oscillator; 2) an input pathway which can alter the phase of the oscillator; and 3) an output such as gene expression, enzyme activity, hormone production, heart rate, body temperature or locomotor activities. The way the oscillator regulates its outputs is complicated, in that on one hand usually the oscillator is not the only factor affecting the outputs, and on …

A Role For Transforming Growth Factor-Beta In Urinary Bladder Dysfunction With Cyclophosphamide-Induced Cystitis, Eric James Gonzalez

Graduate College Dissertations and Theses

Bladder pain syndrome (BPS)/interstitial cystitis (IC) is a chronic pain disorder characterized by at least six weeks of lower urinary tract symptoms and unpleasant sensations (pain, pressure and discomfort) thought to be related to the urinary bladder and not meeting exclusion criteria. While the etiology is not known, BPS/IC may involve a "vicious circle" of uroepithelial dysfunction, inflammation and peripheral and central sensitization. We propose that the urinary bladder inflammatory insult partly mediates voiding dysfunction and visceral neurogenic pain characteristic of BPS/IC. Several studies from our laboratory have already demonstrated the role(s) of cytokines and their downstream targets in the …

Social Buffering By Unfamiliar Adult Males In Preweaning Guinea Pigs (Cavia Pocellus): The Effects On Hpa Activity And Fos Induction In The Medial Prefrontal Cortex, Withayapon Watanasriyakul

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Social buffering, a phenomenon in which the presence of a social partner can reduce stress responses, is often most effective between strongly attached partners. Our laboratory previously found a surprising buffering effect of the hypothalamic-pituitary-adrenal (HPA) response in preweaning guinea pigs by unfamiliar adult males. It was hypothesized that this HPA-buffering effect was driven by social interactions between the two partners and may involve an activation of the prelimbic cortex. Therefore, the current study examined these potential associations. To limit social interactions, the adult male was anesthetized in one condition compared to another condition where the adult male remained conscious. …