Neurosciences Commons^™

An Investigation Of The Role Of Gabab Ligands On Cued And Contextual Fear Conditioning, Chelcie F. Heaney

UNLV Theses, Dissertations, Professional Papers, and Capstones

GABA is the primary inhibitory neurotransmitter in the brain and mediates several processes, including learning and memory. Activating or inhibiting GABA receptors allows for the examination of the effects of altered GABAergic signaling on these processes. The two main receptors, GABAA and GABAB, each have a different mechanism of action when activated, thus they may contribute differentially to learning and memory. The metabotropic GABAB receptor responds with the activation of several intracellular signaling cascades, which provide long-lasting inhibitory effects that primarily mediate network function. Conversely, the GABAA receptor is an ion channel that contributes more immediate inhibitory effects through the …

Neocortical Layer 4 To Layer 2/3 Sensory Information Processing Investigated With Digital-Light-Projection Neuronal Photostimulation, Jason Paul Jerome

Theses and Dissertations (ETD)

The mammalian brain forms neuronal networks and microcircuits with cell-type- and anatomical-specific synaptic connections. Despite great advances in elucidating the cellular physiology of the nervous system, little is known about the computational processes occurring at the level of neuronal microcircuits. Much success has been reported in describing the synaptic input patterns of many brain regions and cell types using photostimulation systems; however, these systems are severely limited in their ability to study the integration of synaptic input from multiple synchronous or temporally correlated presynaptic locations. Here we describe a system that allows the generation of arbitrary 2-D stimulus patterns with …

Phenotypic And Electrophysiologic Characterization Of A Mouse Model Of Fragile X Syndrome, Snigdha Roy

Theses and Dissertations (ETD)

Fragile X syndrome (FXS) is the most common form of inherited mental retardation. It is caused by a mutation in the fragile X mental retardation (FMR1) gene on the X chromosome. Many children with FXS exhibit autistic behaviors and deficits in motor coordination including speech articulation deficits. The development of the FMR1 knockout (Fmr1 KO) mouse, in which the Fmr1 gene is inactivated, has provided an animal model that can be used to investigate underlying neuro-physiological mechanisms associated with FXS as well as to evaluate potential therapeutic treatments. In this study, quantitative behavioral assays were used, such as long term …

Effect Of Synthetic Aβ Peptide Oligomers And Fluorinated Solvents On Kv1.3 Channel Properties And Membrane Conductance, Maria I. Lioudyno, Matteo Broccio, Yuri Sokolov, Suhail Rasool, Jessica Wu, Michael T. Alkire, Virginia Liu, J. Ashot Kozak, Philip R. Dennison, Charles G. Glabe, Mathias Lösche, James E. Hall

Neuroscience, Cell Biology & Physiology Faculty Publications

The impact of synthetic amyloid β (1–42) (Aβ_1–42) oligomers on biophysical properties of voltage-gated potassium channels Kv 1.3 and lipid bilayer membranes (BLMs) was quantified for protocols using hexafluoroisopropanol (HFIP) or sodium hydroxide (NaOH) as solvents prior to initiating the oligomer formation. Regardless of the solvent used Aβ_1–42 samples contained oligomers that reacted with the conformation-specific antibodies A11 and OC and had similar size distributions as determined by dynamic light scattering. Patch-clamp recordings of the potassium currents showed that synthetic Aβ_1–42 oligomers accelerate the activation and inactivation kinetics of Kv 1.3 current with no significant effect …

Predator-Based Fear Conditioning: A Novel Approach To The Study Of The Neurobiology Of Memory, Joshua D. Halonen

USF Tampa Graduate Theses and Dissertations

This series of experiments developed novel paradigms involving the integration of conventional and ethologically relevant forms of reinforcement in the study of fear conditioning in rats. Experiment 1 compared the effects of foot shock, immobilization and predator exposure, alone and in combination, on the expression of conditioned fear memory and extinction. The combination of all 3 reinforcers produced a significantly stronger fear memory and greater resistance to extinction, compared to when each reinforcer was administered alone. Furthermore, whereas conditioning with foot shock, alone, resulted in rapid extinction of the fear memory, the combination of immobilization and cat exposure, or all …

Encoding Of Sensory Prediction Errors In The Human Cerebellum., John Schlerf, Richard B Ivry, Jörn Diedrichsen

Brain and Mind Institute Researchers' Publications

A central tenet of motor neuroscience is that the cerebellum learns from sensory prediction errors. Surprisingly, neuroimaging studies have not revealed definitive signatures of error processing in the cerebellum. Furthermore, neurophysiologic studies suggest an asymmetry, such that the cerebellum may encode errors arising from unexpected sensory events, but not errors reflecting the omission of expected stimuli. We conducted an imaging study to compare the cerebellar response to these two types of errors. Participants made fast out-and-back reaching movements, aiming either for an object that delivered a force pulse if intersected or for a gap between two objects, either of which …

Overexpression Of Serum Response Factor In Astrocytes Improves Neuronal Plasticity In A Model Of Fetal Alcohol Spectrum Disorders, Arco P. Paul

Theses and Dissertations

Neuronal plasticity deficits underlie many of the neurobehavioral problems seen in Fetal Alcohol Spectrum Disorders (FASD). Recently, we showed that third trimester alcohol exposure lead to a persistent disruption in ocular dominance (OD) plasticity. For instance, few days of monocular deprivation results in a robust reduction of cortical regions responsive to the deprived eye in normal animals, but not in ferrets exposed early to alcohol. This plasticity deficit can be reversed if alcohol-exposed animals are treated with a phosphodiesterase type 1 (PDE1) inhibitor during the period of monocular deprivation. PDE1 inhibition can increase cAMP and cGMP levels, activating transcription factors …

Cosmetic Neurology: Enhancement Of The Mind And Attention Deficit Hyperactive Disorder Medication Abuse Among College Students, Mary M. Huff

Senior Honors Theses

Cosmetic neurology is becoming increasingly popular, and it is not just sleep deprived, over worked college students who are interested. People are beginning to seek off-label prescriptions for medications that are typically used to treat disorders such as attention deficit hyperactive disorder (ADHD) or narcolepsy, while researchers are trying to create drugs used solely for mind enhancement purposes. Along with these drugs come many legal and ethical quandaries relating to the regulation of current use as well as the what ifs of future possibilities. A survey was conducted among college students regarding the diagnosis of ADHD, the abuse of ADHD …

Identification Of Bovine Leukemia Virus Tax Function Associated With Host Cell Transcription, Signaling, Stress Response And Immune Response Pathway By Microarray-Based Gene Expression Analysis., Mariluz Araínga, Eri Takeda, Yoko Aida

Journal Articles: Pharmacology & Experimental Neuroscience

BACKGROUND: Bovine leukemia virus (BLV) is associated with enzootic bovine leukosis and is closely related to human T-cell leukemia virus type I. The Tax protein of BLV is a transcriptional activator of viral replication and a key contributor to oncogenic potential. We previously identified interesting mutant forms of Tax with elevated (TaxD247G) or reduced (TaxS240P) transactivation effects on BLV replication and propagation. However, the effects of these mutations on functions other than transcriptional activation are unknown. In this study, to identify genes that play a role in the cascade of signal events regulated by wild-type and mutant Tax proteins, we …

Rapid Perceptual Learning Of Noise-Vocoded Speech Requires Attention, Julia Jones Huyck, Ingrid Johnsrude

Brain and Mind Institute Researchers' Publications

Humans are able to adapt to unfamiliar forms of speech (such as accented, time-compressed, or noise-vocoded speech) quite rapidly. Can such perceptual learning occur when attention is directed away from the speech signal? Here, participants were simultaneously exposed to noise-vocoded sentences, auditory distractors, and visual distractors. One group attended to the speech, listening to each sentence and reporting what they heard. Two other groups attended to either the auditory or visual distractors, performing a target-detection task. Only the attend-speech group benefited from the exposure when subsequently reporting noise-vocoded sentences. Thus, attention to noise-vocoded speech appears necessary for learning.

Cannabinoid Receptor Involvement In Stress-Induced Cocaine Reinstatement: Potential Interaction With Noradrenergic Pathways, Linda K. Vaughn, John R. Mantsch, Oliver Vranjkovic, G. Stroh, M. Lacourt, M. Kreutter, Cecilia J. Hillard

Biomedical Sciences Faculty Research and Publications

This study examined the role of endocannabinoid signaling in stress-induced reinstatement of cocaine seeking and explored the interaction between noradrenergic and endocannabinergic systems in the process. A well-validated preclinical model for human relapse, the rodent conditioned place preference assay, was used. Cocaine-induced place preference was established in C57BL/6 mice using injections of 15 mg/kg cocaine. Following extinction of preference for the cocaine-paired environment, reinstatement of place preference was determined following 6 min of swim stress or cocaine injection (15 mg/kg, i.p.). The role of endocannabinoid signaling was studied using the cannabinoid antagonist AM-251 (3 mg/kg, i.p.). Another cohort of mice …

Catecholamines In The Bed Nucleus Of The Stria Terminalis Reciprocally Respond To Reward And Aversion, Robert A. Wheeler

Biomedical Sciences Faculty Research and Publications

Background

Traditionally, norepinephrine has been associated with stress responses, whereas dopamine has been associated with reward. Both of these catecholamines are found within the bed nucleus of the stria terminalis (BNST), a brain relay nucleus in the extended amygdala between cortical/limbic centers, and the hypothalamic-pituitary-adrenal axis. Despite this colocalization, little is known about subsecond catecholamine signaling in subregions of the BNST in response to salient stimuli.

Methods

Changes in extracellular catecholamine concentration in subregions of the BNST in response to salient stimuli were measured within the rat BNST with fast-scan cyclic voltammetry at carbon-fiber microelectrodes.

Results

A discrete subregional distribution …

The Role Of Calcineurin In Dendritic Remodeling And Epileptogenesis In A Rat Model Of Traumatic Brain Injury, John Campbell

Theses and Dissertations

Traumatic brain injury (TBI), a leading cause of death and disability in the United States, causes potentially preventable damage in part through the dysregulation of neural calcium levels. This dysregulation likely affects the activity of the calcium-sensitive phosphatase, calcineurin, with serious implications for neural function. To test this possibility, the present study characterized the role of calcineurin in a rat model of brain trauma, the lateral fluid percussion injury model. Golgi-Cox histochemistry revealed an acute post-TBI loss and delayed overgrowth of dendritic spines on principal cortical cells. The spine loss appeared to require calcineurin activity, since administering a calcineurin inhibitor, …

L-Tetrahydropalamatine: A Potential New Medication For The Treatment Of Cocaine Addiction, Jia Bei Wang​, John R. Mantsch

Biomedical Sciences Faculty Research and Publications

Levo-tetrahydropalmatine (l-THP) is an active constituent of herbal preparations containing plant species of the genera Stephania and Corydalis and has been approved and used in China for a number of clinical indications under the drug name Rotundine. The pharmacological profile of l-THP, which includes antagonism of dopamine D1 and D2 receptors and actions at dopamine D3, α adrenergic and serotonin receptors, suggests that it may have utility for treating cocaine addiction. In this review, we provide an overview of the pharmacological properties of l-THP and the evidence supporting its development as an anti-addiction medication. The results …

Effects Of Early Alcohol Exposure On Ocular Dominance Plasticity, Crystal Lantz

Theses and Dissertations

Fetal alcohol spectrum disorder is the leading cause of mental retardation in the western world. It is associated with learning and sensory deficits. Some of these deficits are a result of faulty neuronal plasticity. Previously our lab has used ferrets to demonstrate that alcohol exposure during the third trimester of human gestation results in impaired ocular dominance plasticity (ODP). Here we have transferred this model to mice. Mice, treated with 5 mg/kg of ethanol on postnatal days 5, 7 and 9, exhibit a lack of ODP plasticity after 10 days of monocular deprivation (MD) during the critical period of visual …

The Effects Of Oxygen On The Electrophysiology Of Co2/H+-Chemosensitive And -Insensitive Neurons Of The Solitary Complex Of The Rat, Michael Patrick Matott

USF Tampa Graduate Theses and Dissertations

This study tested the hypothesis that decreasing the control O₂ level from 95% to 40% (5% CO₂ + 55% N₂) maintains viability in caudal solitary complex (cSC) neurons in transverse slices (~300-400ꝳ) prepared from neonatal rat (P2-22) maintained at 32-34°C. The underlying rationale is to reduce exposure to redox and nitrosative stimuli generated during several hours of exposure to 95% O₂ that produces a tissue O₂ tension throughout the slice which is in excess of 203 kPa (2.0 atmospheres absolute,ATA) oxygen. Whole cell recordings of cSC neurons maintained in 40% O₂ exhibited spontaneous …

Nanomaterials And Cellular Interaction In The Nervous System, Caleb Joseph Pingel

Student Theses and Dissertations

Nanoparticles (NPs), materials fabricated in nanosize, are being increasingly used due to their unique applications. The potential risks from inhaling NPs and the interaction of inhaled NPs with the peripheral nervous system in rat were determined in this study by investigating 1) retrograde transport of inhaled NP's to the Nodose Ganglion (NDG) neurons, 2) NDG neuronal interaction with NPs in vitro, and 3) the fluid kinetics of NPs in cell sustaining media. Intratracheal intubation and instilling fluorescent NPs with and without a tracer dye (SP-DiOC) showed that NPS were transported from nerve endings in airway to neurons. Exposing NDG neurons …

Hiv-1 Tat Triggers Nuclear Localization Of Zo-1 Via Rho Signaling And Camp Response Element-Binding Protein Activation, Yu Zhong, Bei Zhang, Sung Yong Eum, Michal Toborek

Neurosurgery Faculty Publications

The human immunodeficiency virus (HIV)-specific protein trans-activator of transcription (Tat) can contribute to the dysfunction of brain endothelial cells and HIV trafficking into the brain by disrupting tight junction (TJ) integrity at the blood–brain barrier (BBB) level. Specific TJ proteins, such as zonula occludens (ZO) proteins, localize not only at the cell–cell borders but are also present in the nuclei. The objective of the present study was to evaluate the mechanisms and significance of Tat-induced nuclear localization of ZO-1. Treatment of a brain endothelial cell line (hCMEC/D3 cells) with Tat resulted in a decrease in total levels of ZO-1 but …

Ensembles Of Human Mtl Neurons "Jump Back In Time" In Response To A Repeated Stimulus, M. W. Howard, Indre Viskontas, K. H. Shankar, I. Fried

Psychology

Episodic memory, which depends critically on the integrity of the medial temporal lobe (MTL), has been described as ‘‘mental time travel’’ in which the rememberer ‘‘jumps back in time.’’ The neural mechanism underlying this ability remains elusive. Mathematical and computational models of performance in episodic memory tasks provide a specific hypothesis regarding the computation that supports such a jump back in time. The models suggest that a representation of temporal context, a representation that changes gradually over macroscopic periods of time, is the cue for episodic recall. According to these models, a jump back in time corresponds to a stimulus …

Loss Of Renal Allografts Secondary To Candida Vascular Complications In Two Recipients From The Same Donor, Govardhana R. Yannam, Lucile E. Wrenshall, R. Brian Stevens

Neuroscience, Cell Biology & Physiology Faculty Publications

Infections remain a major cause of morbidity and mortality in transplant patients. Organ recipients are also susceptible to donor-derived pathogens and the majority of donor infections are easily treatable. Rarely, some pathogens have produced life-threatening complications by compromising the vascular anastomosis. In this case series we report loss of two kidney allografts secondary to vascular complications due to Candida albicans. Both recipients received grafts from a common donor, in whom Candida bacteremia in the donor was not apparent at the time of organ acceptance but became apparent on delayed cultures.

Discriminating Famous From Fictional Names Based On Lifetime Experience: Evidence In Support Of A Signal-Detection Model Based On Finite Mixture Distributions., Ben Bowles, Iain M Harlow, Melissa M Meeking, Stefan Köhler

Brain and Mind Institute Researchers' Publications

It is widely accepted that signal-detection mechanisms contribute to item-recognition memory decisions that involve discriminations between targets and lures based on a controlled laboratory study episode. Here, the authors employed mathematical modeling of receiver operating characteristics (ROC) to determine whether and how a signal-detection mechanism contributes to discriminations between moderately famous and fictional names based on lifetime experience. Unique to fame judgments is a lack of control over participants' previous exposure to the stimuli deemed "targets" by the experimenter; specifically, if they pertain to moderately famous individuals, participants may have had no prior exposure to a substantial proportion of the …

Distinct Patterns Of Functional And Effective Connectivity Between Perirhinal Cortex And Other Cortical Regions In Recognition Memory And Perceptual Discrimination., Edward B O'Neil, Andrea B Protzner, Cornelia Mccormick, D Adam Mclean, Jordan Poppenk, Anthony D Cate, Stefan Köhler

Brain and Mind Institute Researchers' Publications

Traditionally, the medial temporal lobe (MTL) is thought to be dedicated to declarative memory. Recent evidence challenges this view, suggesting that perirhinal cortex (PrC), which interfaces the MTL with the ventral visual pathway, supports highly integrated object representations in recognition memory and perceptual discrimination. Even with comparable representational demands, perceptual and memory tasks differ in numerous task demands and the subjective experience they evoke. Here, we tested whether such differences are reflected in distinct patterns of connectivity between PrC and other cortical regions, including differential involvement of prefrontal control processes. We examined functional magnetic resonance imaging data for closely matched …

Deficits On The Clock Drawing Test In Parkinson’S Disease, Ashley Rober

Undergraduate Review

Parkinson’s Disease (PD) is a progressive neurodegenerative disorder that affects 1% of the world population over the age of 65—anywhere from four to six million people (National Parkinson Foundation, 2010). Although most people identify PD as a movement disorder, cognitive deficits are also present. Poor performance on tasks such as set shifting, internal control of attention, and sequencing is commonly reported by PD patients (Stout & Johnson, 2005), as are visual and verbal memory impairments (Moody, Bookheimer, Vanek, & Knowlton, 2004). Visuospatial skills are also problematic, including depth perception, spatial orientation, and spatial organization (Bowen, Burns, Brady, & Yahr, 1972).

Interferon-Α Regulates Glutaminase 1 Promoter Through Stat1 Phosphorylation: Relevance To Hiv-1 Associated Neurocognitive Disorders., Lixia Zhao, Yunlong Huang, Changhai Tian, Lynn Taylor, Norman Curthoys, Yi Wang, Hamilton Vernon, Jialin C. Zheng

Journal Articles: Pharmacology & Experimental Neuroscience

HIV-1 associated neurocognitive disorders (HAND) develop during progressive HIV-1 infection and affect up to 50% of infected individuals. Activated microglia and macrophages are critical cell populations that are involved in the pathogenesis of HAND, which is specifically related to the production and release of various soluble neurotoxic factors including glutamate. In the central nervous system (CNS), glutamate is typically derived from glutamine by mitochondrial enzyme glutaminase. Our previous study has shown that glutaminase is upregulated in HIV-1 infected monocyte-derived-macrophages (MDM) and microglia. However, how HIV-1 leads to glutaminase upregulation, or how glutaminase expression is regulated in general, remains unclear. In …

Statin-Mediated Attenuation Of Chemokine Expression In Peripheral Nerve Vascular Endothelial Cells, Kelly Ann Langert

Dissertations

Pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α), play a pivotal role in the pathogenesis of Guillain-Barré Syndrome (GBS), a debilitating autoimmune disorder that affects the peripheral nervous system. By up-regulating endothelial expression of chemokines and cell adhesion molecules (CAMs), TNF-α facilitates the recruitment and trafficking of autoreactive leukocytes across the blood-nerve barrier and into peripheral nerves, an early pathological hallmark of GBS. Literature indicates that TNF-α, monocyte chemoattractant protein-1 (MCP-1), and intercellular adhesion molecule-1 (ICAM-1) are locally increased in patients with GBS, correlating with disease severity. Similar findings have been demonstrated in an animal model of GBS, experimental autoimmune neuritis …

Forebrain Noradrenergic Alterations And Anxiety After Myocardial Infarction, Jaimee Glasgow

Dissertations

Thirty to 45% of patients who suffer a myocardial infarction (MI) develop anxiety disorders and/or depression, and the development of mood and anxiety disorders following MI is a major risk factor for cardiovascular morbidity and mortality. Depressed post-MI patients have an increased risk of fatal arrhythmias, which are often precipitated by emotional stressors. However, the central nervous system mechanisms that contribute to post-MI anxiety and arrhythmia susceptibility are unknown. Therefore, the studies reported in this dissertation were designed to test the hypothesis that alterations in noradrenergic transmission in the forebrain contribute to the development of anxiety disorders and arrhythmia susceptibility …

Electronic Nose Based On Independent Component Analysis Combined With Partial Least Squares And Artificial Neural Networks For Wine Prediction, Teodoro Aguilera, Jesús Lozano, José A. Paredes, Francisco J. Alvarez, José I. Suárez

Neuroscience, Cell Biology & Physiology Faculty Publications

The aim of this work is to propose an alternative way for wine classification and prediction based on an electronic nose (e-nose) combined with Independent Component Analysis (ICA) as a dimensionality reduction technique, Partial Least Squares (PLS) to predict sensorial descriptors and Artificial Neural Networks (ANNs) for classification purpose. A total of 26 wines from different regions, varieties and elaboration processes have been analyzed with an e-nose and tasted by a sensory panel. Successful results have been obtained in most cases for prediction and classification.

Electrophysiological Abnormalities In Sod1 Transgenic Models In Amyotrophic Lateral Sclerosis: The Commonalities And Differences, Sherif M. Elbasiouny, Katharina Quinlan, Tahra L. Eissa, Charles J. Heckman

Neuroscience, Cell Biology & Physiology Faculty Publications

Since its first description in 1874 by Charcot, the hallmark feature of ALS is the progressive degeneration of upper and lower motoneurons (Charcot, 1874). In the spinal cord, motoneuron degeneration starts long before symptom onset and advances in a size-related fashion, in which large-size alpha-motoneurons degenerate first followed by small-size alpha-motoneurons (Pun et al., 2006; Hegedus et al., 2007; Hegedus et al., 2008). There are conflicting reports regarding the survival of the smallest-sized spinal motoneurons, the gamma-motoneurons (Swash and Fox, 1974; Sobue et al., 1981). Despite its original description, the neuronal degeneration in ALS is not limited to motoneurons. Recent …

Seroprevalencia De Pestivirus De Rumiantes En Ovinos Reproductores De Una Empresa De La Sierra Central Del Perú, Nathalie A. Llancares, Hermelinda G. Rivera, Mariluz Araínga, Nestor Falcon P.

Journal Articles: Pharmacology & Experimental Neuroscience

The aim of the present study was to determine the prevalence of Bovine Viral Diarrhea Virus (BVDV) and Border Disease virus (BDV) in breeding sheep from a large cooperative farm in the Central highlands of Peru. Blood samples from apparently healthy sheep of 4 years old, both sexes (female = 165; male = 165) were collected for antibodies detection against BVDV and BDV using the virus neutralization test. The 2.1 ± 1.5% (7/330) and 28.5 ± 4.9% (94/330) of breeding sheep had antibodies against BVDV and BDV respectively, with antibodies titers of 1:2 and 1:16. There was significant association between …

Determination Of The Molecular Mechanisms Of Hyperglycemia-Induced Changes In Cav3.2 Calcium Channel Properties, Ginny Marie Keeling

Master's Theses

Hyperglycemia can cause altered excitability due to increased CaV3.2 T-type calcium channel function, bestowing diabetics an increased neuropathy risk. The objective of this study was to understand the molecular mechanisms of increased CaV3.2 function during hyperglycemia in vitro, which leads to a 58% increase in current density and increased channel open probability (PO), among other changes. Two major findings are reported in this study:

1) The enzymatic elimination of extracellular N-acetylneuraminic acid (NANA) moieties reversed the increase in current density and the shift in PO, showing that hyper-glycosylation alters channel function in disease.

2) Treatment with GM1 (a ganglioside highly …