Life Sciences Commons^™

Over-Expression Of Copper/Zinc Superoxide Dismutase In The Median Preoptic Nucleus Attenuates Chronic Angiotensin Ii-Induced Hypertension In The Rat., John P. Collister, Mitch Bellrichard, Donna Drebes, David Nahey, Jun Tian, Matthew C. Zimmerman

Journal Articles: Cellular & Integrative Physiology

The brain senses circulating levels of angiotensin II (AngII) via circumventricular organs, such as the subfornical organ (SFO), and is thought to adjust sympathetic nervous system output accordingly via this neuro-hormonal communication. However, the cellular signaling mechanisms involved in these communications remain to be fully understood. Previous lesion studies of either the SFO, or the downstream median preoptic nucleus (MnPO) have shown a diminution of the hypertensive effects of chronic AngII, without providing a clear explanation as to the intracellular signaling pathway(s) involved. Additional studies have reported that over-expressing copper/zinc superoxide dismutase (CuZnSOD), an intracellular superoxide (O2·-) scavenging enzyme, in …

The Effect Of Maternal Aldosterone Levels On The Expression Of 11b-Hsd Isoenzymes In Normal And Hypertensive Rat Placentae, Nicole Jorissen

Journal of Undergraduate Research at Minnesota State University, Mankato

In this project, we developed a Western blotting procedure to semi-quantitate levels of 11β-HSD1 and 11β-HSD2 in whole cell extracts. Then, we applied this technique to analyze the effect of reduced maternal aldosterone levels on the expression of 11β-HSD1 and 11β-HSD2 isoenzymes in the placental tissue in both normal and hypertensive rats. These enzymes control levels of glucocorticoids which compete for aldosterone’s mineralocorticoid receptor. Overstimulation of this receptor results in hypertension. If aldosterone levels decrease, levels of the enzymes controlling active glucocorticoid concentrations might change to compensate for the lowered aldosterone levels. Decreased placental 11β-HSD2 expression could affect hypertension in …

Utility Of Anthropometric Measures In A Multiethnic Population: Their Association With Prevalent Diabetes, Hypertension And Other Chronic Disease Comorbidities, Heather P. Tarleton, Lisa V. Smith, Zuo-Feng Zhang, Tony Kuo

Health and Human Sciences Faculty Works

Body mass index (BMI) and waist circumference (WC) are two common anthropometric measures of obesity in clinical and public health practice. Consensus, however, remains elusive regarding their utility for predicting cardiovascular disease risk in multiethnic populations. We address this gap in the literature by analyzing cross-sectional data from the first round of the Los Angeles County Health and Nutrition Examination Survey, 2011. We characterized the relationships between BMI, WC, waist-to-hip ratios, waist-to-height ratios, and chronic disease extent, as confirmed by the presence of hypertension, diabetes, and/or two or more other chronic conditions as defined by a composite indicator ‘comorbidity’. To …

Allelic Variability In The Cyp11b2 C344t Single Nucleotide Polymorphism From A Cohort Of East Africans, Spencer Wright

Mahurin Honors College Capstone Experience/Thesis Projects

Non-communicable disease (NCD), in particular cardiovascular disease, is a significant problem in developing countries. Essential hypertensions (EH) is a leading risk factor for vascular disease and while managing EH in developing countries is considered a high global priority, few studies exist from third world populations. From a cohort of Kenyans living in the Kasigau region, we have investigated the allele frequency of a single nucleotide polymorphism (SNP) previously reported to correlate with salt-sensitive EH. The SNP being investigated is aldosterone synthase CYP11B2 C344T (rs1799998), a polymorphism in the renin-angiotensin system (RAS). The C344T polymorphism is located in the promoter region …

Hub City Steps: A 6-Month Lifestyle Intervention Improves Blood Pressure Among A Primarily African-American Community, Jamie M. Zoellner, Carol Connell, Michael B. Modson, Jessica L. Thomson, Alicia S. Landry, Elaine Fontenot Molaison, Vickie Blakely Reed, Kathleen Yadrick

Faculty Publications

The effectiveness of community-based participatory research (CBPR) efforts to address the disproportionate burden of hypertension among African Americans remains largely untested. The objective of this 6-month, noncontrolled, pre-/post-experimental intervention was to examine the effectiveness of a CBPR intervention in achieving improvements in blood pressure, anthropometric measures, biological measures, and diet. Conducted in 2010, this multicomponent lifestyle intervention included motivational enhancement, social support provided by peer coaches, pedometer diary self-monitoring, and monthly nutrition and physical activity education sessions. Of 269 enrolled participants, 94% were African American and 85% were female. Statistical analysis included generalized linear mixed models using maximum likelihood estimation. …

Orexin, Cardio-Respiratory Function, And Hypertension, Aihua Li, Eugene Nattie

Dartmouth Scholarship

In this review we focus on the role of orexin in cardio-respiratory functions and its potential link to hypertension. (1) Orexin, cardiovascular function, and hypertension. In normal rats, central administration of orexin can induce significant increases in arterial blood pressure (ABP) and sympathetic nerve activity (SNA), which can be blocked by orexin receptor antagonists. In spontaneously hypertensive rats (SHRs), antagonizing orexin receptors can significantly lower blood pressure under anesthetized or conscious conditions. (2) Orexin, respiratory function, and central chemoreception. The prepro-orexin knockout mouse has a significantly attenuated ventilatory CO₂ chemoreflex, and in normal rats, central application of orexin stimulates …

Muscle Metaboreflex Control Of Cardiovascular Function In Hypertension, Marty Daniel Spranger

Wayne State University Dissertations

Skeletal muscle ischemia during or immediately following exercise leads to the accumulation of metabolites (e.g., lactate, proton and diprotonated phosphate) which activate chemoreceptive afferents within the muscle leading to a reflex increase in sympathetic outflow generating substantial increases in mean arterial pressure (MAP), cardiac output (CO) and heart rate (HR) - termed the muscle metaboreflex. When the reflex is activated during submaximal dynamic exercise, the pressor response occurs via increased CO with no net peripheral vasoconstriction. When metaboreflex activation is sustained during the recovery from exercise (i.e., post-exercise muscle ischemia - (PEMI)), whereas MAP remains elevated for as long as …

An Analysis Of Abnormal Electrocardiograms In First And Second Year Medical School Students, Molly Anne Kalish

PCOM Biomedical Studies Student Scholarship

The high stress level placed upon medical school students, particularly during their first and second didactic years, may have a negative effect on their health. Although surveys and subjective questionnaires have been used to evaluate the effects medical school has upon a student’s cardiovascular health, there has been little clinical data obtained to confirm this notion. The aim of this longitudinal study was to demonstrate whether any abnormal cardiovascular parameters, specifically QTc wave interval, cardiac axis vector and blood pressure abnormalities, could be documented to occur in two different classes of medical students during their first two years. Such information …

Pathway Analysis Approaches For Rare And Common Variants: Insights From Genetic Analysis Workshop 18, Stella Aslibekyan, Marcio Almeida, Nathan L. Tintle

Faculty Work Comprehensive List

Pathway analysis, broadly defined as a group of methods incorporating a priori biological information from public databases, has emerged as a promising approach for analyzing high-dimensional genomic data. As part of Genetic Analysis Workshop 18, seven research groups applied pathway analysis techniques to whole-genome sequence data from the San Antonio Family Study. Overall, the groups found that the potential of pathway analysis to improve detection of causal variants by lowering the multiple-testing burden and incorporating biologic insight remains largely unrealized. Specifically, there is a lack of best practices at each stage of the pathway approach: annotation, analysis, interpretation, and follow-up. …

The Role Of Nitric Oxide Scavenging In Hemoglobin-Based Oxygen Carrier Induced Hypertension: Systemic And Microvascular Effects, Alan Ottarson

Theses and Dissertations

The purpose of this study was to identify the effects of a hemoglobin-based oxygen carrier, HBOC-201, on the cardiovascular system. Systemic cardiovascular parameters of mean arterial pressure (MAP), pulse pressure, heart rate, and oxygen saturation, as well as vascular resistance, were examined. A murine model of the cardiovascular system and microvasculature was employed. Sprague-Dawley rats (male; 230-530g; N = 13) were anaesthetised and surgically prepared for intravital microscopy of the spinotrapezius muscle. Increasing doses of HBOC-201 (2 mg/kg, 22 mg/kg, 230 mg/kg, and 780 mg/kg) and an iso-oncotic volume control were administered to assess for a dose-response relationship. MAP displayed …

Renal Humoral, Genetic And Genomic Mechanisms Underlying Spontaneous Hypertension, Jason A. Collett

Theses and Dissertations--Biology

In spite of significant progress in our knowledge of mechanisms that control blood pressure, our understanding of the pathogenesis of hypertension, its genetics, and population efforts to control blood pressure, hypertension remains the leading risk factor for mortality worldwide. It’s estimated that 1 out of every 3 adults has hypertension. Hypertension is a major risk factor for cardiovascular disease and stroke, and is considered a primary or contributing cause of death to more than 2.4 million US deaths each year. Although spontaneous hypertension has been the subject of substantial research, many critical questions remain unanswered.

To investigate mechanisms underlying spontaneous …