Behavioral Neurobiology Commons^™

Behavioral And Histological Inflammatory Analysis Of A Single, Mild Traumatic Brain Injury And Repeated Subconcussive Brain Injury Using A Rodent Model., Anna Marie Clay

Theses and Dissertations

Subconcussive (SC) impacts have become a growing concern within the neuroscience community regarding the immediate and long-lasting effects of sports-related injuries. While a single low-level impact, i.e., a subconcussion, may not cause cerebral perturbations, it has been increasingly recognized that repeated SC exposure can induce deleterious effects. Therefore, determining the lower limits of systematic perturbation resulting from multiple SC impacts is of critical importance in expanding our understanding of cerebral vulnerability and recovery. Currently, there is a lack of correlation between a mild traumatic brain injury (mTBI) and repeated SC impacts with respect to injury biomechanics. Moreover, the cumulative threshold …

Mirnas Levels In A Streptozocin Model Of Alzheimer’S Disease, Nada Moustafa

Theses and Dissertations

Dementia entails a progressive decrease in cognitive functions, with 50%-75% of cases attributed to Alzheimer’s disease (AD); an aging-associated condition characterized by the build-up of tangled phosphorylated Tau (p-Tau) protein and beta-amyloid (Aβ) depositions. Sporadic AD (sAD) is multifactorial in nature, resulting from a combination of environmental and genetic predisposing factors. Type 2 diabetes mellitus (T2DM) is a leading risk factor for dementia, and deregulation of brain glucose metabolism is associated with early cognitive affection in sAD. Thus, the diabetogenic agent Streptozotocin (STZ) is used to experimentally create an AD model in animals (STZ-induced sAD), in which abnormalities in cerebral …

Chronic Adolescent Stress As A Predictive Factor For The Risk Of Developing Ptsd-Like Symptoms In Adulthood, Grace K. Young

Theses and Dissertations

Post-traumatic stress disorder is a stress and trauma based psychological disorder that is defined by the DSM-IV as an anxiety disorder that affects approximately 7.8% of people in the United States. PTSD is when those who suffer a traumatic event have intense and distressing feelings, emotions, and memories for a prolonged period of time after the event. A prominent feature of PTSD is the impaired ability to properly extinguish a fear response after a dangerous trigger or stressor is no longer present, also known as safety learning. Stressors are threats perceived within the environment that activate a response within the …

Viral Injection Of Rna Polymerase Ii-Interacting Protein Rprd2 In The Nucleus Accumbens Induces Anxiety-Like Behavior In Mice, Hannah E. Woolard

Theses and Dissertations

Anxiety and its related disorders have become increasingly prevalent as more awareness and acceptance of mental illnesses have come to fruition, especially in the light of the ongoing COVID-19 pandemic. Anxiety can affect anyone regardless of their age, sex, or social status and is currently the most commonly diagnosed mental illness worldwide (Bandelow & Michaelis, 2015). While there are several effective treatments available, the underlying brain mechanisms that cause anxiety are still largely unknown and further research continues to piece together the complex pathophysiology behind this disease. The use of laboratory animal models, such as mice, to induce and observe …

Glucocorticoid Receptor Dysregulation Underlies 5-Ht2a Receptor-Dependent Synaptic And Behavioral Deficits In A Mouse Neurodevelopmental Disorder Model, Justin M. Saunders

Theses and Dissertations

Schizophrenia is a severe neuropsychiatric disorder that presents with diverse symptoms, some of which remain resistant to treatment. Increased risk of neurodevelopmental disorders such as schizophrenia has been observed following gestational infection in humans, leading to development of maternal immune activation (MIA) animal models. Increased density of the serotonin 5-HT2AR receptor (5-HT2AR), the primary target of hallucinogenic drugs and a key target of atypical antipsychotics, has been observed in postmortem antipsychotic-free prefrontal cortex samples from schizophrenia subjects, a change reflected in frontal cortex of adult MIA offspring. To model MIA, we administered 20 mg/kg i.p. of the viral mimetic poly-(I:C) …

Investigating Cannabinoid Type-1 Receptor (Cb1r) Positive Allosteric Modulators (Pams) In Mouse Models Of Overt Cannabimimetic Activity, Subjective Drug Effects, And Neuropathic Pain, Jayden Elmer

Theses and Dissertations

Chronic pain affects between 20 and 30 percent of the adult population in western countries and represents a wide array of specific etiologies (Berge, 2011). Neuropathic pain secondary to traumatic nerve injury, chemotherapeutic toxicity, or diseases (e.g., diabetes mellitus) is often refractory to conventional analgesics, with patients receiving less than 50% pain relief compared to placebo (Finnerup et al. 2010). The endocannabinoid system has shown potential as a therapeutic target for neuropathic pain wherein CB1 agonism via administration of exogenous agonists or pharmacological blockade of endocannabinoid catabolic enzymes exhibits efficacy in reversing allodynia in the chronic constriction injury (CCI) model …

Role Of Clic4 And The Synaptic Transcriptome In The Behavioral And Molecular Neurobiology Of Ethanol, Rory M. Weston

Theses and Dissertations

Alcohol use disorder (AUD) is a prevalent neuropsychiatric disease with profound health, social, and economic consequences. With an estimated 50% heritability, identifying genes that engender risk and contribute to the underlying neurobiological mechanisms represents an important first step in developing effective treatments. Gene expression studies are an important source of candidate genes for studying AUD, providing windows into the molecular machinery engaged by the brain in response to ethanol. Published studies have identified chloride intracellular channel 4 (Clic4) as an ethanol-regulated gene in brain capable of modulating sensitivity to sedation in multiple species. The functions of Clic4 are …

Validation Of Ninein As An Ethanol-Related Quantitative Trait Gene: Reassessment, Design, And Functional Validation Of Reference Genes For Qpcr Analysis Of Brain Tissue In Mice, Jessica L. Jurmain

Theses and Dissertations

The increasing use of quantitative real-time polymerase chain reaction (qPCR) as a method for quantifying gene expression has led to an increased demand for standardization of data analysis methods to ensure accurate reporting and robust, reproducible results. The exponential nature of qPCR amplification results in the potential magnification of what are usually very small sources of error. Relative gene expression calculations circumvent this issue by normalizing target gene expression data to within-sample expression of a previously validated, stably expressed reference gene or genes. Multiple studies discussed herein have found that qPCR data are more reliable and reproducible when multiple reference …

Contextually Modulated Avoidance Behavior In Rats Post-Pavlovian Extinction, Lauren Branigan

Theses and Dissertations

The following study sought to examine the psychological substrates of renewal (e.g.., context dependent extinction processes) for conditioned avoidance behaviors in rats. Using signaled active avoidance conditioning, rats acquired two-way shuttle responding, to two different auditory stimuli. These behaviors were then extinguished through exposure to the auditory stimuli where shuttling behavior was now without consequence. Subjects were then tested for renewal of avoidance in three distinct renewal sequences (e.g., ABA vs ABB, AAB vs AAA, and ABC vs ABB) in three separate groups of rats. It was found that subjects showed more responding to a stimulus presented outside of its …

Molecular Targets Of Psychedelics And Their Role In Behavioral Models Of Hallucinogenic Action, Hiba Z. Vohra

Theses and Dissertations

Psychedelics are a subset of hallucinogenic drugs that exert their characteristic effects through agonist activity at the serotonin receptor 2A (5-HT_2A). In this study, I aimed to characterize the modulatory role of the metabotropic glutamate subtype 2 receptor (mGluR2) in the 5-HT_2A-specific rodent model of hallucinogenic action, head-twitch response (HTR). Secondly, I aimed to explore if 5-HT_2A agonist-induced deficits in prepulse inhibition (PPI) of the startle response, an additional model of hallucinogenic action, could be produced in mice. Though 5-HT_2A agonist-induced PPI deficits, which represent interruptions in normal sensorimotor gating, have been described in …

An Investigation Of Vocal Learning Propensity In Zebra Finch (Taeniopygia Guttata), Tatsuya Hayashi

Theses and Dissertations

The investigator attempted to predict the vocal learning propensity from either family pedigree or early vocal babbling (subsong). Pedigree trees suggest the possibility that vocal learning ability may depend on family. We failed to predict vocal learning propensity from subsong, but suggested that subsong may influence vocal learning outcome.

Complexities Of Chronic Opioid Exposure, Maciej Gonek

Theses and Dissertations

Studies on repeated exposure to opioids have been carried out for decades yet the mechanisms for certain phenomena such as tolerance are still not fully understood. Furthermore, different medications, such as frequently prescribed benzodiazepines, or different disease states, such as HIV, have their own effects and interactions with chronic opioid exposure that are not fully understood. The overall objective of this dissertation was to investigate the complexities of chronic opioid exposure and how different disease states and medications may modulate the effects of chronic opioids. Our findings demonstrate that the administration of diazepam, at doses that are not antinociceptive or …

Spatial Learning And Memory In Brain-Injured And Non-Injured Mice: Investigating The Roles Of Diacylglycerol Lipase-Α And -Β., Lesley D. Schurman

Theses and Dissertations

A growing body of evidence implicates the importance of the endogenous cannabinoid 2-arachidonyl glycerol (2-AG) in memory regulation. The biosynthesis of 2-AG occurs primarily through the diacylglycerol lipases (DAGL-α and -β), with 2-AG serving as a bioactive lipid to both activate cannabinoid receptors and as a rate limiting precursor for the production of arachidonic acid and subsequent pro-inflammatory mediators. Gene deletion of DAGL-α shows decrements in synaptic plasticity and hippocampal neurogenesis suggesting this biosynthetic enzyme may be important for processes of normal spatial memory. Additionally, 2-AG is elevated in response to pathogenic events such as traumatic brain injury (TBI), suggesting …

Role Of Mitochondrial Beta-Oxidation In Ethanol Response: A Candidate Gene Study Using Caenorhabditis Elegans, Harini Pallikarana Tirumala

Theses and Dissertations

Alcohol use disorder (AUD) is the fourth leading cause of preventable death in the United States, and the fifth leading risk factor for premature death and disability, globally. There are currently very few treatment options for AUD and there is a need for effective preventive and treatment strategies for this condition. AUD risk has a significant hereditary component, with the contribution of genetic factors being estimated to be about 50%. The Davies-Bettinger laboratory uses C. elegans as a model organism to study the contribution of genetic factors in modulating neuronal responses to ethanol. In this project, we examined the role …

N-Alkyl 4-Methylamphetamine Enantiomers And The Implication For Potential Modulation Of Abuse Liability And Enhancement Of Psychoactive Drug Targeting., Ramsey Sitta

Theses and Dissertations

Drugs of abuse have a long history in humanity. Currently however, a subject of great interest is the phenylalkylamine family of drugs. Not only is the abuse liability of interest but also the potential therapeutic expansion of the capabilities of this family of drugs by utilizing the unique stereospecific effects of the newly discovered hybrid compounds. Based upon prior data of N-Alkyl 4-MA the enantiomers of N-Methyl, N-Ethyl, and N-Propyl were analyzed in hDAT, hNET, and hSERT. It was found that there was a negative correlation between chain length and potency and dopaminergic component. In agreement with the currently established …

Protein Kinase M Zeta-Mediated Ltp Maintenance In The Non-Human Primate Hippocampus: A Role For Stress And Serotonergic Signaling In Affective Processing, Sasha L. Fulton

Theses and Dissertations

Early-Life Stress (ELS) is associated with vulnerability to mood disorder, but it’s not well understood how ELS contributes to deficits in cognitive function. Atypical PKMzeta is critical for LTP maintenance and memory. The current study aims to characterize the ELS phenotype with respect to this key marker of hippocampal LTP.

A Neural Circuit Of Appetite Control In C. Elegans, Kristen C. Davis

Theses and Dissertations

Feeding behavior and its associated neural circuitry is complex and intricate in mammalian systems, however, a simple model organism, such as C. elegans provides a more basic approach to understand factors and molecules involved. The fruit-dwelling nematode provides a unique set of resources; it only consists of 959 cells, 302 of which are neurons. In addition, each neuron’s connectivity and position within the worm is known and consistent between animals. Conservation of neurotransmitters and biochemical processes add to this impressive list. These resources provide an excellent background to address feeding behavior and the neural structures governing it.

Feeding behavior in …

Acute And Chronic Effects Of Inhalants In Intracranial Self-Stimulation, Matthew Tracy

Theses and Dissertations

Inhalants are a loosely defined diverse group of volatile substances which people abuse. Despite widespread misuse of inhalants, there are limited preclinical methods available to study the reinforcement-like properties of inhalants. One procedure which has demonstrated substantial promise as a tool to investigate inhalant pharmacology is the intracranial self-stimulation (ICSS) procedure. ICSS utilizes pulses of electrical stimulation to the mesolimbic reward pathway to serve as a temporally defined and controlled operant reinforcer with a highly adjustable efficacy. The first aim of the project was to characterize the effects of commonly abused inhalants: including toluene, trichloroethane, nitrous oxide, isoflurane and R134a …

Cyclic Gmp: A Satiety Signal In C. Elegans, Ji S. Park

Theses and Dissertations

Appetite control and satiety mechanisms help animals maintain energy homeostasis; however, these mechanisms can be misregulated, leading to overweight and obesity. Caenorhabditis elegans is an excellent model system to study appetite and satiety because of its conserved behavioral aspects of satiety and conserved molecular mechanisms. ASI senses nutrition and its activity is required for the behavioral state of satiety quiescence. The purpose of this thesis project was to elucidate the function of cGMP signaling in ASI by looking at behavioral effects from the pharmacological use of sildenafil (Viagra), a PDE inhibitor, and the effects on ASI activation from mutating guanylyl …