Medicine and Health Sciences Commons^™

Investigation To Examine The Profile Of Auditory Brainstem And Hearing Thresholds Using Tone Burst Audiometry Brainstem Response In A Preclinical Migraine Model, Megan Huelsing

MSU Graduate Theses

Migraine is a disabling neurological disease that is characterized by prominent auditory symptoms, including hyperacusis, which is defined as extreme sensitivity to sounds. The goal of this study was to investigate changes in hearing sensitivity and neural changes in the brainstem by measuring neural activity of the auditory brainstem in an established preclinical model of chronic migraine. To induce a chronic migraine state within the trigeminal system, male and female Sprague Dawley rats were subjected to three known human risk factors including neck muscle tension and REM sleep deprivation that promote latent sensitization, and exposure to a pungent odor, which …

Distribution Of Erm Proteins In The Stomach Mucosa Of Normal And Diabetic Rats, Asmaa Salem Al Sereidi

Theses

Diabetes mellitus (DM), or simply diabetes, refers to a group of metabolic disorders that include a variety of diseases that disrupt our body's metabolism. The long-term uncontrolled disease can lead to stomach complications such as gastroparesis, as well as disruption in several proteins, such as ERM (Ezrin, radixin, moesin) proteins. ERM proteins are three proteins that are structurally and functionally related. ERM proteins have molecular masses of 82, 80, and 75 kDa, respectively. Ezrin is highly expressed in the stomach, especially in parietal cells that secrete gastric acid. ERM proteins function as scaffolding proteins in lipid rafts and granule trafficking …

Assessment Of Executive Function Using A Series Of Operant Conditioning Based Tasks In T1dm Rodents, Kevin T. Murphy

Electronic Thesis and Dissertation Repository

This study examined the impact of Type 1 Diabetes Mellitus (T1DM) on executive function using a series of operant conditioning based tasks in rats. Sprague Dawley rats were randomized to either non-diabetic (n = 12; 6 male) or diabetic (n = 14; 6 male) groups. Diabetes was induced using multiple low-dose streptozotocin injections. All diabetic rodents were insulin-treated using subcutaneous insulin pellet implants. At week 14 of the study, rats were placed on a food restricted diet to induce 5 - 10% weight loss. Rodents were familiarized and tested on a series of tasks that required continuous adjustments to novel …

Lipocalin-2 Ameliorates The Signs And Outcomes Of Diabetes Mellitus In An Animal Model, Saeeda Mohammed Al Jaberi

Theses

Lipocalin-2 (LCN2) is a new adipocytokine consisting of 198 amino acids. It is also referred to as neutrophil gelatinase-associated lipocalin, siderocalin, uterocalin, α1-microglobulin related protein, or 24p3. LCN2 belongs to a large group of transport proteins that are capable of carrying small and lipid soluble molecules in blood circulation. It has two membrane receptors, megalin/glycoprotein GP330, which binds human LCN2 and SLC22A17 or 24p3R, which forms complexes with mouse Lcn2 protein. LCN2 is encoded by a gene located at chromosome locus 9q34.11. LCN2 was initially isolated from neutrophil granules released at site of infection and inflammation in human and from …

Lipocalin-2 Ameliorates The Signs And Outcomes Of Diabetes Mellitus In An Animal Model, Saeeda Mohammed Al Jaberi

Theses

Lipocalin-2 (LCN2) is a new adipocytokine consisting of 198 amino acids. It is also referred to as neutrophil gelatinase-associated lipocalin, siderocalin, uterocalin, α1-microglobulin related protein, or 24p3. LCN2 belongs to a large group of transport proteins that are capable of carrying small and lipid-soluble molecules in blood circulation. It has two membrane receptors, megalin/glycoprotein GP330, which binds human LCN2 and SLC22A17 or 24p3R, which forms complexes with mouse Lcn2 protein. LCN2 is encoded by a gene located at chromosome locus 9q34.11. LCN2 was initially isolated from neutrophil granules released at the site of infection and inflammation in humans and from …

Effects Of Acute And Chronic Nicotine Administration On Choice Of Probabilistic Outcomes, Katya A. Nolder

Graduate Theses, Dissertations, and Problem Reports

Risky choice can be operationally defined as the choice for a larger, uncertain reinforcer over a smaller, certain reinforcer. Research suggests smokers engage in more risky or maladaptive decisions when compared to nonsmokers. The relation between nicotine and risky choice could benefit from further investigation, since nicotine is the active substance of tobacco products that maintains tobacco addiction. Acute nicotine administration has shown to alter risky choice; however, since the everyday smoker uses nicotine repeatedly, more research on chronic administration is warranted and would allow for assessment of tolerance or sensitization of these effects. The present study investigated effects of …

Evaluation Of Tracing Techniques In The Rat Spinal Cord Using A Custom Matlab Application., Rachel M. Zalla

Electronic Theses and Dissertations

The objective of this research project is to evaluate the efficiency of traditional chemical tracing compared to dual-viral tracing for labeling long ascending propriospinal neurons (LAPNs) in the uninjured rat spinal cord, and to develop a MATLAB program which will accurately quantify this labeling.

To evaluate chemical tracing, Fluoro-Ruby (FR) was injected at the level of the axon terminals, and the number of ipsilateral labeled cell bodies at lumbar level was quantified. Similarly, two dual-viral systems were evaluated, by either injecting retro-AAV-Cre or HiRet-Lenti-Cre unilaterally in combination with a Cre-dependent adeno-associated virus. The HiRet-Lenti and FR groups labeled significantly greater …

Understanding Water Diffusion In Experimental Spinal Cord Injury Remote From Injury Epicenter, Alice Motovylyak

Dissertations (1934 -)

Diffusion tensor imaging (DTI) has demonstrated success as a biomarker of spinal cord injury (SCI) severity as shown from numerous preclinical studies. However, artifacts from stabilization hardware at the lesion have precluded its use for longitudinal assessments. Previous research has documented ex vivo diffusion changes in the spinal cord both caudal and rostral to the injury epicenter. The aim of this dissertation was to quantify the structural changes that lead to different diffusion measures in the rat cervical spinal cord after a thoracic contusion injury in an attempt to find a biomarker of injury. Animals received a thoracic contusion injury …

Compressed Sensing For Few-View Multi-Pinhole Spect With Applications To Preclinical Imaging, Benjamin Michael Rizzo

Dissertations (1934 -)

Single Photon Emission Computed Tomography (SPECT) can be used to identify and quantify changes in molecular and cellular targets involved in disease. A radiopharmaceutical that targets a specific metabolic function is administered to a subject and planar projections are formed by imaging emissions at different view angles around the subject. The reconstruction task is to determine the distribution of radioactivity within the subject from the projections. We present a reconstruction approach that utilizes only a few view angles, resulting in a highly underdetermined system, which could be used for dynamic imaging applications designed to quantify physiologic processes altered with disease. …

Biochemical And Biological Effects Of Irisin In A Model Of Diabetes Mellitus, Mohamed Omer Sirelkhatim Mahgoub

Dissertations

Diabetes mellitus (DM) is a highly prevalent health problem affecting more than 425 million people worldwide. It is associated with several detrimental complications such as neuropathy, nephropathy, retinopathy and cardiovascular diseases. Irisin is a novel hormone that plays a role in metabolism by stimulating the browning of white adipose tissue (WAT) into beige adipose tissue which acquires properties that are similar to those of brown adipose tissue (BAT). Several studies have attempted to characterize the roles of irisin in DM and obesity, however, contradictory results have been reported and physiological roles of irisin have been questioned by several researchers. In …

Bone Loss Quantification Following Extraction In Rats: A Foundation For Grafting And Regenerative Studies, Emily Willett

Theses & Dissertations

Background: Loss of the alveolar ridge width and height following extraction is well-documented and several techniques, including grafting, have been proposed to reduce bone loss. Purpose: To characterize the pattern of bone turnover and inflammation after extraction and to initiate a study of the effect of grafting and local administration of simvastatin (SIM). Methods: Thirty-two retired-breeder rats underwent extraction of the right maxillary first molar and standard surgical defect creation under inhalation anesthesia. The left side of each animal served as the unmanipulated control. Comparison of groups (n=8, ANOVA) was done at days 0, 7, 14, and …

An In Vivo Study Of The Effects Of Perinatal Caffeine Exposure On Synaptic Efficacy In The Hippocampus Of Freely Moving Adult Rats, Jee Eun Park

Senior Theses and Projects

The synapse from the perforant path to the dentate gyrus has been widely used successfully to demonstrate long-term potentiation, a cellular model underlying learning and memory. Caffeine is one of the most widely consumed psychoactive stimulants in the world. Caffeine consumption increases in alertness, improvements in motor skills, and neurological functions, and these effects have promoted its use throughout history. Although the many short term cognitive benefits of caffeine intake are well understood, the long term effects of caffeine exposure have been widely disputed. Despite this, it is estimated that over 80% of women continue to consume caffeine throughout pregnancy. …

Chronic Stress Potentiates The Response To Intra-Bed Nucleus Of The Stria Terminalis (Bnst) Pituitary Adenylate Cyclase Activating Peptide (Pacap) Infusion., Steven Bradley King

Graduate College Dissertations and Theses

Chronic or repeated exposure to stressful stimuli can result in several maladaptive consequences, including increased anxiety-like behaviors and altered peptide expression in brain structures involved in emotion. Among these structures, the bed nucleus of the stria terminalis (BNST) has been implicated in emotional behaviors as well as regulation of hypothalamic-pituitary-adrenal (HPA) axis activity. In rodents, chronic variate stress (CVS) has been shown to increase BNST pituitary adenylate cyclase activating polypeptide (PACAP) and its cognate PAC1 receptor transcript, and BNST PACAP signaling may mediate the maladaptive changes associated with chronic stress. In order to determine whether chronic stress would potentiate the …

Interaction Between Angiotensin Ii And Bdnf In Modulating Sympathetic Nerve Activity, Bryan K. Becker

Theses & Dissertations

Over activation of the sympathetic nervous system is prevalent in many forms of cardiovascular disease such as chronic heart failure (CHF) and hypertension. Although increased neuronal renin-angiotensin system activity in presympathetic neurons has been well implicated in mediating this sympatho-excitation, many of the neuronal effects of angiotensin II (Ang II) signaling remain poorly understood. One particular mechanism of Ang II-mediated increases in presympathetic neuronal activity is through reductions in voltage-gated K⁺ currents. Another pathway that has profound effects on neuronal K⁺ currents and that has been previously implicated in Ang II-signaling is brain-derived neurotrophic factor (BDNF) activity through …

Systemic Insulin Sensitivity And Skeletal Muscle Akt Signaling In Rats Artificially Selected For Low And High Aerobic Capacity, Kyle Levi Fulghum

MSU Graduate Theses

The mechanism(s) linking physical inactivity, obesity, and type-II diabetes are unclear. I hypothesized low intrinsic aerobic capacity is associated with reduced systemic insulin sensitivity via skeletal muscle insulin signaling. After 34 generations of selective breeding, high aerobic capacity (HCR) rats exhibited an 8-fold increase in running distance vs low aerobic capacity (LCR) rats (n=14 per group). LCR rats had higher rates of weight gain vs HCR (p<0.05) though food consumption was constant (p=0.86) over a 12-week study. Rats were divided into 4 groups: 1) LCR-Sham Surgery, 2) LCR-Catheterization, 3) HCR-Sham Surgery or 4) HCR-Catheterization (n=7 per group). Euglycemic-hyperinsulinemic clamps on catheterized rats tested insulin sensitivity while sham LCR and HCR were used for basal tissue analysis. Plasma insulin levels did not differ during the clamps, but LCR required lower glucose infusion rates than HCR (p<0.05). Upon insulin stimulation, both absolute and normalized phospho-Akt(Ser473) of soleus muscle were significantly increased in HCR above basal group (p<0.05), but not in LCR. No difference was observed between insulin-stimulated phospho-Akt(Ser473) of HCR and LCR groups . These data support that LCR is linked to a reduction in insulin sensitivity in vivo without impairments of insulin-stimulated skeletal muscle phospho-Akt(Ser473) vs HCR rats.

Local Modulation And Measurement Of Macrophage-Derived Bioactive Proteins From Implanted Biomaterials In Rat, Geetika Bajpai

Graduate Theses and Dissertations

Fibrosis around the implanted medical devices is a severe problem that can plague long-term device reliability. Activation of macrophage phenotype (macrophage polarization) has emerged as a new and possible means for reducing fibrosis in the fields of biomaterials and regenerative medicine. Macrophages are phagocytic cells that respond to microenvironmental cues that direct their phenotype. Macrophage activation has been widely studied in mouse and human in the context of tumor biology, yet little information is available regarding how macrophage activation could be used in a biomaterials context. Further, rats rather than mice are the common subjects in biomaterials experiments. A significant …

Experimental Investigation On The Relationship Between Lead Exposure And Thyroids In Diabetes., Salah Sumar Ali Al-Zadjali

Dissertations

Lead exposure can cause multiple systemic toxicities, particularly affecting the hematopoietic, nervous and renal systems. However, its effects on the thyroid functions are not well elucidated and the published studies are controversial. In addition, although there are several experimental thyroid models, each one of them has its own limitations. According, in this dissertation, we investigated the possible relationship between lead exposure, thyroid functions and short-term systemic toxicity in two animal models, namely normal (non-diabetic) and diabetic animals. We also investigated the possibility of developing a hormonal thyroid model.

In the non-diabetic model, Wistar rats were divided into five groups and …

Experimental Investigation On The Relationship Between Lead Exposure And Thyroids In Diabetes, Salah Sumar Ali Al-Zadjali

Dissertations

Lead exposure can cause multiple systemic toxicities, particularly affecting the hematopoietic, nervous and renal systems. However, its effects on the thyroid functions are not well elucidated and the published studies are controversial. In addition, although there are several experimental thyroid models, each one of them has its own limitations. Accordingly, in this dissertation, we investigated the possible relationship between lead exposure, thyroid functions and short-term systemic toxicity in two animal models, namely normal (non-diabetic) and diabetic animals. We also investigated the possibility of developing a hormonal thyroid model. In the non-diabetic model, Wistar rats were divided into five groups and …

Determining The Critical Window Of Influence Of Pcb Perinatally On Behavioral And Hormonal Development In Sprague-Dawley Rat Pups, Natalie Sommerville, Lee A. Meserve, Howard C. Cromwell

Honors Projects

Polychlorinated biphenyls (PCB) had widespread use in the United States in commercial manufacturing in the United States until the late 1970s. Even though they were banned, measurable amounts can still be found in the environment and food sources. PCB has known effects on altering hormone development and behavior in the species Rattus norvegicus. To determine the most crucial developmental time of exposure to PCB in Sprague-Dawley rat pups, rat pups were exposed to PCB at differing weeks of either gestation period or the first postnatal week. Behavioral tests were performed for the different rat pups, as well as blood …

Glial Cell Modulators And Associated Anti-Inflammatory Activity: Implications In Reducing Methamphetamine Abuse-Related Behaviors In Rodents, Sarah Snider

Theses and Dissertations

Methamphetamine is a psychomotor stimulant that produces hyperactivity and euphoria and can lead to drug-seeking and abuse. An estimate from 2005 put the cost of methamphetamine abuse to society at an estimated 23.4 billion dollars. One of methamphetamine's effects is activation of glial cells and associated neuroinflammatory activity in the periphery and CNS. Glia are responsible for maintaining calcium homeostasis, neuroplasticity, immune activity, and cell signaling. Activation of glia and neuroinflammation are becoming recognized as links in drug abuse-related behavior. The goal of the present work was to assess the ability of ibudilast, AV1013, and minocycline, three glial cell modulating …

Effect Of Cannabinoids On Pain-Stimulated And Pain-Depressed Behavior In Rats, Andrew Kwilasz

Theses and Dissertations

Cannabinoids produce antinociception in many preclinical models of acute and chronic pain. In contrast, cannabinoids produce inconsistent analgesia in humans, showing little or no efficacy in treating acute pain, with modest efficacy in treating chronic inflammatory pain. This discrepancy may reflect an overreliance on preclinical assays of pain-stimulated behaviors, defined as behaviors that increase in rate or intensity following delivery of a noxious stimulus. In these assays, antinociception is indicated by a reduction in pain-stimulated behaviors, and antinociception is produced either by a reduction in sensory sensitivity to the noxious stimulus (i.e. true analgesia) or by false positive motor impairment. …

Predicting Vision Loss In Healthy Aging With Manganese-Enhanced Mri Of The Rat Eye, David Bissig

Wayne State University Dissertations

In healthy aging, visual function declines throughout adulthood. Age-related changes in neuronal ion homeostasis -- specifically, increased Ca2+ influx through L-type voltage gated calcium channels (L-VGCCs) -- are believed to contribute to certain functional declines, but this possibility has not yet been tested in the neural retina. In young, mid- and old adult Long-Evans rats, we compared visual function (optokinetic tracking), as well as retinal physiology and eye morphology (Mn2+-enhanced MRI (MEMRI), which uses neuronal Mn2+ uptake as a marker of Ca2+ influx). We documented significant age-related decreases in visual performance and increases in retinal ion influx. We confirmed that …

Nicotine Sensitization In A Rodent Model Of Schizophrenia: A Comparison Of Adolescents, Adults, And Neurotrophic Factors., Marla Kay Perna

Electronic Theses and Dissertations

The behavioral effects of nicotine on locomotor activity in a rodent model of psychosis were analyzed. This model is based on neonatal quinpriole treatment (a dopamine D2/D3 agonist) which causes increased D2 receptor sensitivity, a phenomenon known as D2 priming that is common in schizophrenia. D2-primed adolescent rats did not demonstrate nicotine-induced hypoactivity early in training, and males demonstrated more rapid sensitization to nicotine as compared to controls administered nicotine. D2-primed females administered nicotine demonstrated increased stereotypic behavior. D2-primed adult rats given nicotine demonstrated significantly more robust sensitization to nicotine than controls given nicotine. Brain-derived neurotrophic factor (BDNF) was analyzed …