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Full-Text Articles in Physiology

Microglia Distribution In The Lateral Ventricles Following Treatment Of Lysolecithin Model Of Multiple Sclerosis, Spencer James Wilson Jan 2022

Microglia Distribution In The Lateral Ventricles Following Treatment Of Lysolecithin Model Of Multiple Sclerosis, Spencer James Wilson

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Multiple sclerosis (MS) affects an estimated one million people in the US alone (Wallin et al., 2019). We modeled MS in rats using lysolecithin injection into the corpus callosum to diminish motor function unilaterally through demyelination, meanwhile treating the injury with Fluoxetine, Ibuprofen, and ascorbic acid (FIAA) to increase neurogenesis and oligodendrogenesis. Motor function was assessed using the Montoya Staircase test pre- and post-surgery. Motor capabilities recovered in the contralateral limb, but not in the ipsilateral, and recovery was not significantly affected by treatment. We identified microglia by CX3CR1 and examined its distribution in the adult neurogenic niche, the SVZ …


Evaluation Of A Monosynaptic Spinal Circuit In Multiple Mouse Models Of Amyotrophic Lateral Sclerosis, Maura A. Curran Jan 2022

Evaluation Of A Monosynaptic Spinal Circuit In Multiple Mouse Models Of Amyotrophic Lateral Sclerosis, Maura A. Curran

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Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease. To date, there are no significant disease-modifying treatments, and one limiting factor in treatment is the amount of time it takes for a patient to receive a diagnosis of ALS. This study examined multiple mouse models before symptom onset to help identify early changes in a reflex circuit of ALS mice. Dorsal root stimulation of the sacral spinal cord in multiple models ALS mouse models showed changes in the resulting ventral root compound action potential amplitude, latency, and ability to maintain synaptic depression. These data also suggest that a mouse model …


Use Of Forelimb Asymmetry In The Analysis Of Cns Recovery From A Demyelination Event, Joseph C. Hinkle Jan 2022

Use Of Forelimb Asymmetry In The Analysis Of Cns Recovery From A Demyelination Event, Joseph C. Hinkle

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Using forelimb asymmetry analysis along with Montoya Staircase methodology we tested how a fluoxetine simvastatin ascorbic acid drug cocktail would affect recovery from a demyelinating event in a rat model, with the hypothesis that if administered then it would help female recovery but hinder male recovery. It was found that a fluoxetine simvastatin and ascorbic acid drug cocktail did not significantly enhance recovery from a demyelination model injury in female rats, and that the same drug cocktail significantly slowed male rat recovery from the same type of injury. It was also apparent that the more effective methodology for investigating this …


Effects Of Fluoxetine/Simvastatin/Ascorbic Acid Combination Treatment On Neurogenesis And Functional Recovery In A Model Of Multiple Sclerosis, Olivia Cameron Webb Jan 2021

Effects Of Fluoxetine/Simvastatin/Ascorbic Acid Combination Treatment On Neurogenesis And Functional Recovery In A Model Of Multiple Sclerosis, Olivia Cameron Webb

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Whereas immune modulation has proven beneficial in multiple sclerosis (MS), we hypothesized that targeting down-stream modulators of neurogenesis and subsequent remyelination may offer an additional, if not superior, point of intervention in an attempt to repair damage and recover lost function. As such, the present study assessed the effectiveness of 30-day administration of the drug combination fluoxetine (5 mg/kg), simvastatin (1 mg/kg), and ascorbic acid (50 mg/kg) (FSA) on an early marker of neurogenesis, doublecortin (DCX), and functional recovery using the Montoya Staircase following lysolecithin-induced focal demyelination of the corpus callosum in middle-aged (10-11 month) male and female rats. Lysolecithin …


A Novel Method For Analysis Of Proprioceptor Sensory Neuron Subtypes In The Mouse Dorsal Root Ganglia, Delaney C. Grant Jan 2021

A Novel Method For Analysis Of Proprioceptor Sensory Neuron Subtypes In The Mouse Dorsal Root Ganglia, Delaney C. Grant

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Proprioceptive sensory neurons encode critical mechanosensory information that helps determine how the body interacts with the outside world and monitors the proper execution of motor movements. Housed in skeletal muscles lie specialized mechanoreceptors that are critical to this feedback loop: muscle spindles supplied by group Ia & group II afferents, and Golgi tendon organs supplied by group Ib afferents relay information regarding changes in muscle force, length, and tension. All three afferent subtypes originate in the muscle and travel to the dorsal root ganglia, relaying information to the central nervous system. GTO and MS proprioceptive afferent subtypes have been identified, …


Potential Involvement Of Micro Vesicle Particles In The Synergistic Effects Of Ultraviolet-B Radiation And Platelet -Activating Factor Receptor Agonists On Cytokine Production, Shweta Bhadri Jan 2021

Potential Involvement Of Micro Vesicle Particles In The Synergistic Effects Of Ultraviolet-B Radiation And Platelet -Activating Factor Receptor Agonists On Cytokine Production, Shweta Bhadri

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Cytokines play a pivotal role in regulating inflammation, which is a condition that makes the tissue vulnerable to different pathological and physiological conditions. Thus, how cytokines are regulated is an important area of study. Skin that receives ultraviolet B radiation (UVB), a major pro-oxidative stressor, results in the release of multiple cytokines and chemokines like tumor necrosis factor (TNF)-alpha and interleukin (IL)-8. Previous studies from our group and others have demonstrated synergistic release of TNF-alpha when UVB is combined with IL-1 or the lipid mediator Platelet-activating factor (PAF). Of interest, subcellular microvesicle particles (MVP) have been proposed to play an …


Extracellular Vesicles From Uvb Irradiated Keratinocytes Contain Cyclobutane Pyrimidine Dimers, Meghana Reddy Ginugu Jan 2021

Extracellular Vesicles From Uvb Irradiated Keratinocytes Contain Cyclobutane Pyrimidine Dimers, Meghana Reddy Ginugu

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Ultraviolet (UV) radiation induces the formation of cyclobutane pyrimidine dimers (CPDs) in genomic DNA, which are normally removed by nucleotide excision repair. However, the fate of these adducts remain largely unexplored. Detection of these photoproducts in body fluids could act as a predictor of UV exposure and enable a better understanding of the pathogenesis of photosensitive skin diseases, such as lupus. Using cultured human keratinocytes exposed to UVB radiation in vitro, ultracentrifugation of cell culture supernatants, and immunodot blot analysis of isolated DNA, we have found that a small fraction of CPDs is released from cells in a dose- and …


Exploring The Impact Of Affective Processing On Visual Perception Of Large-Scale Spatial Environments, Auroabah S. Almufleh Jan 2020

Exploring The Impact Of Affective Processing On Visual Perception Of Large-Scale Spatial Environments, Auroabah S. Almufleh

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This thesis explores the interaction between emotions and visual perception using large scale spatial environment as the medium of this interaction. Emotion has been documented to have an early effect on scene perception (Olofsson, Nordin, Sequeira, & Polich, 2008). Yet, most popularly-used scene stimuli, such as the IAPS or GAPED stimulus sets often depict salient objects embedded in naturalistic backgrounds, or “events” which contain rich social information, such as human faces or bodies. And thus, while previous studies are instrumental to our understanding of the role that social-emotion plays in visual perception, they do not isolate the effect of emotion …


Divalent Metal Cation Entry And Cytotoxicity In Jurkat T Cells: Role Of Trpm7 Channels, Alayna N. Mellott Jan 2020

Divalent Metal Cation Entry And Cytotoxicity In Jurkat T Cells: Role Of Trpm7 Channels, Alayna N. Mellott

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Humans are exposed daily to a variety of metals that can be harmful to our immune system. Although certain divalent metal cations are essential for numerous cellular functions and are critical trace elements in humans, the uptake mechanisms of these ions remain mostly unknown. Transient receptor potential melastatin 7 (TRPM7), which is expressed in a variety of human cell types, including lymphocytes and macrophages, conducts many divalent metal cations. TRPM7 channels are largely inactive under normal physiological conditions due to cytoplasmic magnesium acting as a channel inhibitor. Magnesium is a cofactor for many biochemical reactions. Low serum levels of magnesium, …


Artificially-Generated Scenes Demonstrate The Importance Of Global Properties During Early Scene Perception, Mavuso Wesley Mzozoyana Jan 2020

Artificially-Generated Scenes Demonstrate The Importance Of Global Properties During Early Scene Perception, Mavuso Wesley Mzozoyana

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During scene perception, studies have shown the importance of the global distribution of a scene. Electrophysiological studies have found these global effects concentrated corresponding to the second positive and first negative peaks (P2 and N1, respectively) of the Event-related potential (ERP) during the first 600 ms of scene perception. We sought to understand in Experiment 1, to what extent early responses to scenes were driven by mid-level global information such as the degree of naturalness or openness in a scene image in the absence of specific low-and high-level information (color and semantic object detail). This was done using artificially-generated stimuli …


Protocol Development And Optimization For Rnls Mouse Characteristic Assessment, Hasan Farid Jan 2020

Protocol Development And Optimization For Rnls Mouse Characteristic Assessment, Hasan Farid

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Protocol development and optimization are vital in the scientific method process. By having accurate protocols, one can properly assess the characteristics of their animal model for any given experiment. One animal newly adopted in our lab was the novel regulatable nuclear localization sequence (rNLS) mouse model. This novel mouse model displays symptoms of Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal dementia (FTD), after the accumulation of the hTDP-43 (TAR DNA-binding protein 43) aggregate in the central nervous system. The expression of this protein occurs after the removal of deoxycycline from the mouse’s food source. Once the removal of the drug, this …


Trpm7 Channels As A Bioassay Of Internal And External Mg2+, Charles T. Luu Jan 2019

Trpm7 Channels As A Bioassay Of Internal And External Mg2+, Charles T. Luu

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Magnesium is an important divalent metal cation that is involved in numerous cellular functions. The details of cellular Mg2+ regulation, homeostasis and transport remain unclear. Magnesium transporter protein (MagT1) is a Mg2+ transporter and deficiency of this protein has been reported to lead to impaired Mg2+ influx and a decreased cytoplasmic [Mg2+]. Transient receptor potential melastatin 7 (TRPM7) is a ubiquitously expressed membrane protein containing a channel pore and a C-terminal alpha-type serine/threonine protein kinase domain. Importantly, TRPM7 channel is believed to conduct both Mg2+ and Ca2+. In the present study, we investigated if TRPM7 can be used as a …


Effect Of Administration Of Somatostatin Analogue On Blood Pressure In Chronic Intermittent Hypoxic Rats, Kajal Kamra Jan 2019

Effect Of Administration Of Somatostatin Analogue On Blood Pressure In Chronic Intermittent Hypoxic Rats, Kajal Kamra

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The cardiorespiratory system in our bodies does not adapt to Chronic Intermittent Hypoxia (CIH) and consequently syndromes such as sleep apnea lead to pathophysiological conditions like Hypertension. It has been demonstrated that the peripheral chemoreceptors underpin the development of these conditions and at present, there are no selective drug therapies for this form of hypertension. However, evidence suggests that peripheral chemoreflex sensitivity to CO2 & hypoxia is reduced by Somatostatin (SST) in humans. Our preliminary in-vitro studies have demonstrated that SST will blunt the response of the carotid body to hypoxia and decrease the baseline activity of the carotid body. …


Is Mitochondrial Development Impaired In Hyperoxic Rats And Does This Underpin The Blunting Of The Acute Hypoxic Ventilatory Response?, Tariq Hasan Fayyad Jan 2017

Is Mitochondrial Development Impaired In Hyperoxic Rats And Does This Underpin The Blunting Of The Acute Hypoxic Ventilatory Response?, Tariq Hasan Fayyad

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Carotid body (CB) responses to hypoxia are low at birth and increase over time to mature responses. Using an in vitro rat CB-carotid sinus nerve (CSN) preparation, Kholwadwala and Donnelly (1992) demonstrated that the CSN activity in response to hypoxia increased from low levels to robust adult responses after two weeks. This time course of maturation was paralleled by an increase in TASK channel sensitivity to hypoxia in the O2-sensing Type I cells (Kim et al, 2011). Previous studies have indicated that a fall in Type I cell mitochondrial volume and an increase in the rate of oxidative phosphorylation may …


Cx43 Expression Increases In Response To Increased Temperature Incubation In The Developing Chicken Embryonic Brain, Erick A. Barrios Jan 2017

Cx43 Expression Increases In Response To Increased Temperature Incubation In The Developing Chicken Embryonic Brain, Erick A. Barrios

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We used the chicken embryo model to examine whether altered incubation temperature during chicken embryo development would alter the protein expression of heat shock protein 70 (hsp70), hsp90, and connexin 43 (cx43) in the brain. We incubated eggs in either optimal (37.6° C, Con), increased (39.6° C, +2), or decreased (35.6° C, -2) temperature conditions until they reached embryonic day 16 (E16). The -2 condition significantly increased incidence of embryonic mortality. As shown in the literature, the development of the eggs was accelerated or decelerated due to increased or decreased temperature respectively. To control for this, we incubated eggs at …


The Hypercapnic Ventilatory Response And Behavior In Ca2+-Activated K+ (Bk) Channel Knock Out Mice And T-Cell Death-Associated Gene 8 (Tdag8) Receptor Knock Out Mice, Christine Annette Ratliff-Rang Jan 2017

The Hypercapnic Ventilatory Response And Behavior In Ca2+-Activated K+ (Bk) Channel Knock Out Mice And T-Cell Death-Associated Gene 8 (Tdag8) Receptor Knock Out Mice, Christine Annette Ratliff-Rang

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Some acid sensing areas in the brain control the expression of breathing and anxiety/fear including the locus coeruleus (LC) (Redmond & Huang, 1979) and the nucleus tractus solitarius (NTS). It has been found that knocking out T-cell death-associated gene 8 (TDAG8), a chemosensor, attenuates CO2 induced fear phenotypes in mice. However their hypercapnic ventilatory response (HCVR) has not yet been looked at. Also, BK channels are large-conductance, calcium-activated potassium channels that are activated by increases in concentration of intracellular calcium ions. It has been found that BK KO rats have an increase in their HCVR (Patrone et al., 2014) however …


Upstream Regulators Of Vrac Activation In Human 1321n1 Astrocytoma Cells, Courtney Elyse Moore Jan 2017

Upstream Regulators Of Vrac Activation In Human 1321n1 Astrocytoma Cells, Courtney Elyse Moore

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Cells rely on a constant volume not only for structural stability but also for normal homeostatic processes to occur. In the brain and CNS, cells can regain their normal volume through a process termed regulatory volume decrease (RVD). A key component of a cells' response to cell swelling is the activation of channel(s) responsible for the efflux of chloride current, ICl,swell. Volume regulated anion channels (VRAC) which mediate ICl,swell have been implicated in controlling cell volume during RVD, but the mechanisms which activate this channel are not completely understood. In this study, I examined the role of G protein-coupled signaling …


Investigating The Role Of An Sk Channel Activator On Survival And Motor Function In The Sod1-G93a, Als Mouse Model, Matthew Thomas Dancy Jan 2017

Investigating The Role Of An Sk Channel Activator On Survival And Motor Function In The Sod1-G93a, Als Mouse Model, Matthew Thomas Dancy

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Amyotrophic Lateral Sclerosis (ALS) is a fatal, adult-onset progressive degenerative motor neuron disease that is characterized by muscle atrophy and weakness due to the loss of upper and lower motor neurons. Average survival time for individuals diagnosed with the disease is three to five years; currently there is no cure and only one drug approved by the Food and Administration (FDA). Scientists have proposed various theories in order to solve the mystery which surrounds ALS. One of these theories hypothesizes how hyperexcitability and excitotoxicity leads to the death of motor neurons. In this study, we will address ways of combatting …


Cx43 Expression Increases In Response To Increased Temperature Incubation In The Developing Chicken Embryonic Brain, Erick A. Barrios Jan 2017

Cx43 Expression Increases In Response To Increased Temperature Incubation In The Developing Chicken Embryonic Brain, Erick A. Barrios

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We used the chicken embryo model to examine whether altered incubation temperature during chicken embryo development would alter the protein expression of heat shock protein 70 (hsp70), hsp90, and connexin 43 (cx43) in the brain. We incubated eggs in either optimal (37.6°C, Con), increased (39.6°C, +2), or decreased (35.6°C, -2) temperature conditions until they reached embryonic day 16 (E16). The -2 condition significantly increased incidence of embryonic mortality. As shown in the literature, the development of the eggs was accelerated or decelerated due to increased or decreased temperature respectively. To control for this, we incubated eggs at optimal temperature (37.6°C) …


The Effect Of Aging On The Blood Brain Barrier Permeability And Response To Fluoxetine Enantiomers, Ethar Arkan Jan 2017

The Effect Of Aging On The Blood Brain Barrier Permeability And Response To Fluoxetine Enantiomers, Ethar Arkan

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We tested the effect of the fluoxetine enantiomers (S-fluoxetine and R-fluoxetine) versus Prozac (50:50 ratio of R- and S- fluoxetine enantiomers) and/or control on blood brain barrier (BBB) permeability in different brain regions in both male and female rats. The rats consumed orally the drug (5 mg/kg) or vehicle for a total of three days, then were injected with sterile Evans blue dye ip, at least 12 hours before euthanasia.. We see significant regional brain differences in BBB permeability (hippocampus has tighter BBB), significant differences based on the age of the animals (young rats show enhanced permeability in lower brain …


Measuring The Effects Of High-Fat Diet On Breathing And Oxygen-Sensitivity Of The Carotid Body Type I Cell, Ryan J. Rakoczy Jan 2017

Measuring The Effects Of High-Fat Diet On Breathing And Oxygen-Sensitivity Of The Carotid Body Type I Cell, Ryan J. Rakoczy

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The carotid bodies (CB), the primary peripheral chemoreceptors, respond to changes in blood gases with neurotransmitter release, thereby increasing carotid sinus nerve firing frequency and ultimately correcting the pattern of breathing. It has previously been demonstrated that acute application of the adipokine leptin caused perturbations of intracellular calcium and membrane ion movement in isolated CB Type I cells (Pye et al, 2015) and augmented the response of the intact CB to hypoxia (Pye et al, 2016). This study's aim was to examine, in-vivo, if elevated leptin modulated CB function and breathing. Rats were fed high-fat chow or control chow for …


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 Jan 2016

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 …


The Use Of Doublecortin To Quantify The Effects Of Pharmacological Treatment On Neurogenesis And Functional Recovery After Stroke, Amber Lee Hensley Jan 2016

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 Jan 2016

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 Jan 2016

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 …


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 Jan 2016

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. …


Effect Of Somatostatin On Voltage-Gated Calcium Influx In Isolated Neonatal Rat Carotid Body Type I Cells, Eric J. Dunn Jan 2015

Effect Of Somatostatin On Voltage-Gated Calcium Influx In Isolated Neonatal Rat Carotid Body Type I Cells, Eric J. Dunn

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Somatostatin (SST) is a neuropeptide hormone that regulates the release of secondary hormones. Evidence suggests SST plays a neuromodulatory role due to its distribution throughout the central nervous system. Interestingly, SST has been suggested to affect the carotid body, the small peripheral chemoreceptors that regulate breathing. It has been shown that the peripheral chemoreflex sensitivity to CO2 and hypoxia is reduced by SST in humans (Pedersen et al., 1999; Pandit et al., 2014). SST has also been found to inhibit whole cell Ca2+ currents recorded from adult rat carotid body type I cells (e Silva & Lewis, 1995), but the …


Effects Of Sleep Deprivation On Performance In A Water Radial Arm Maze (Wram) Task, Saline Hughes Jan 2015

Effects Of Sleep Deprivation On Performance In A Water Radial Arm Maze (Wram) Task, Saline Hughes

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Sleep deprivation causes many adverse effects on work performance. Many experiments in both human and rodent models reveal detriments that sleep deprivation has on learning and memory, including performance in a water radial arm maze (WRAM) task. This study utilizes the modified multiple platform method (MMPM) of sleep deprivation; rats were sleep deprived in order to study memory errors they may make during the WRAM task. The findings indicate that 6 hours of sleep deprivation for 2 five-day week periods did not affect performance in the WRAM task except on the initial day compared to the large platform group. The …


Factors Determining The Effects Of Human Interaction On The Cortisol Levels Of Shelter Dogs, Regina M. Willen Jan 2015

Factors Determining The Effects Of Human Interaction On The Cortisol Levels Of Shelter Dogs, Regina M. Willen

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Dogs admitted to animal shelters experience psychological stressors resulting in elevated plasma cortisol. We previously found 30 min of human interaction reduced this response. The present study further characterized this effect, with the aim of developing a practical means of reducing stress of shelter dogs. We found that a second day of 30 min of petting reduced cortisol levels as effectively as the first. Further, 15 min of this interaction was as effective as 30 min. During petting, signs of excitation (vocalizations) and anxiety (panting) as well as escaped attempts were reduced, and social solicitation (tail-wagging) increased. However, cortisol levels …


The Effect Of Scalp Tissue On Current Shunting During Anodal Transcranial Direct Current Stimulation (Tdcs), Mark Patrick Jackson Jan 2015

The Effect Of Scalp Tissue On Current Shunting During Anodal Transcranial Direct Current Stimulation (Tdcs), Mark Patrick Jackson

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Transcranial Direct Current Stimulation (tDCS) has been used to treat various mental and neurological illnesses. Rodent models have been used to examine physiological changes in the brain after tDCS, as well as to develop safety standards. However, most animal tDCS studies implant an electrode on the brain, potentially altering the path of current during stimulation. Additionally, no studies have been completed specifically examining maximum safe anodal tDCS limits, and a pilot study conducted to determine an electrode montage to examine biological changes of learning and memory from anodal tDCS indicated brain lesion was occurring before a commonly cited lesion threshold …