Metabolic and Cardiac Responses to Temperature in the Lizard Dipsosaurus dorsalis

1958 ◽  
Vol 31 (2) ◽  
pp. 100-111 ◽  
Author(s):  
William R. Dawson ◽  
George A. Bartholomew
Keyword(s):  
Cardiac Responses ◽  
Dipsosaurus Dorsalis

scholarly journals Linking metabolic dysfunction with cardiovascular diseases: Brn-3b/POU4F2 transcription factor in cardiometabolic tissues in health and disease

2021 ◽  
Vol 12 (3) ◽  
Author(s):  
Vishwanie S. Budhram-Mahadeo ◽  
Matthew R. Solomons ◽  
Eeshan A. O. Mahadeo-Heads
Keyword(s):  
Transcription Factor ◽  
Cardiovascular Diseases ◽  
Cell Fate ◽  
Target Genes ◽  
Cardiovascular Responses ◽  
Normal Function ◽  
Valuable Insight ◽  
Metabolic Dysfunction ◽  
Pathological Changes ◽  
Cardiac Responses

AbstractMetabolic and cardiovascular diseases are highly prevalent and chronic conditions that are closely linked by complex molecular and pathological changes. Such adverse effects often arise from changes in the expression of genes that control essential cellular functions, but the factors that drive such effects are not fully understood. Since tissue-specific transcription factors control the expression of multiple genes, which affect cell fate under different conditions, then identifying such regulators can provide valuable insight into the molecular basis of such diseases. This review explores emerging evidence that supports novel and important roles for the POU4F2/Brn-3b transcription factor (TF) in controlling cellular genes that regulate cardiometabolic function. Brn-3b is expressed in insulin-responsive metabolic tissues (e.g. skeletal muscle and adipose tissue) and is important for normal function because constitutive Brn-3b-knockout (KO) mice develop profound metabolic dysfunction (hyperglycaemia; insulin resistance). Brn-3b is highly expressed in the developing hearts, with lower levels in adult hearts. However, Brn-3b is re-expressed in adult cardiomyocytes following haemodynamic stress or injury and is necessary for adaptive cardiac responses, particularly in male hearts, because male Brn-3b KO mice develop adverse remodelling and reduced cardiac function. As a TF, Brn-3b regulates the expression of multiple target genes, including GLUT4, GSK3β, sonic hedgehog (SHH), cyclin D1 and CDK4, which have known functions in controlling metabolic processes but also participate in cardiac responses to stress or injury. Therefore, loss of Brn-3b and the resultant alterations in the expression of such genes could potentially provide the link between metabolic dysfunctions with adverse cardiovascular responses, which is seen in Brn-3b KO mutants. Since the loss of Brn-3b is associated with obesity, type II diabetes (T2DM) and altered cardiac responses to stress, this regulator may provide a new and important link for understanding how pathological changes arise in such endemic diseases.

scholarly journals Mindfulness Dampens Cardiac Responses to Motion Scenes of Violence

Mindfulness ◽  
2017 ◽  
Vol 9 (2) ◽  
pp. 575-584 ◽  
Author(s):  
Artur Brzozowski ◽  
Steven M. Gillespie ◽  
Louise Dixon ◽  
Ian J. Mitchell
Keyword(s):  
Cardiac Responses

scholarly journals The Influence ofNrf2on Cardiac Responses to Environmental Stressors

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Reuben Howden ◽  
Eva Gougian ◽  
Marcus Lawrence ◽  
Samantha Cividanes ◽  
Wesley Gladwell ◽  
...  
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
High Frequency ◽  
Low Frequency ◽  
Therapeutic Strategies ◽  
Environmental Stressors ◽  
Total Power ◽  
Airborne Pollutants ◽  
Cardiac Responses

Nrf2protects the lung from adverse responses to oxidants, including 100% oxygen (hyperoxia) and airborne pollutants like particulate matter (PM) exposure, but the role ofNrf2on heart rate (HR) and heart rate variability (HRV) responses is not known. We hypothesized that genetic disruption ofNrf2would exacerbate murine HR and HRV responses to severe hyperoxia or moderate PM exposures.Nrf2-/-andNrf2+/+mice were instrumented for continuous ECG recording to calculate HR and HRV (low frequency (LF), high frequency (HF), and total power (TP)). Mice were then either exposed to hyperoxia for up to 72 hrs or aspirated with ultrafine PM (UF-PM). Compared to respective controls, UF-PM induced significantly greater effects on HR (P<0.001) and HF HRV (P<0.001) inNrf2-/-mice compared toNrf2+/+mice.Nrf2-/-mice tolerated hyperoxia significantly less thanNrf2+/+mice (~22 hrs;P<0.001). Reductions in HR, LF, HF, and TP HRV were also significantly greater inNrf2-/-compared toNrf2+/+mice (P<0.01). Results demonstrate thatNrf2deletion increases susceptibility to change in HR and HRV responses to environmental stressors and suggest potential therapeutic strategies to prevent cardiovascular alterations.

The impact of menopausal status on cardiac responses to exercise training and lower body negative pressure

Maturitas ◽  
2017 ◽  
Vol 103 ◽  
pp. 91
Author(s):  
Amanda Q.X. Nio ◽  
Eric J. Stöhr ◽  
Samantha Rogers ◽  
Rachel Mynors-Wallis ◽  
Jane M. Black ◽  
...  
Keyword(s):  
Exercise Training ◽  
Negative Pressure ◽  
Lower Body Negative Pressure ◽  
Menopausal Status ◽  
Lower Body ◽  
Cardiac Responses ◽  
The Impact

Histochemical determination of the fiber composition of locomotory muscles in a lizard,Dipsosaurus dorsalis

1980 ◽  
Vol 214 (3) ◽  
pp. 303-309 ◽  
Author(s):  
Robert W. Putnam ◽  
Todd T. Gleeson ◽  
Albert F. Bennett
Keyword(s):  
Fiber Composition ◽  
Dipsosaurus Dorsalis

Abstract 12689: Cardiovascular Responses to Energy Drinks in a Healthy Population: The C-energy Study

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Teri M Kozik ◽  
Mouchumi Bhattacharyya ◽  
Teresa T Nguyen ◽  
Therese F Connolly ◽  
Walther Chien ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Systolic Blood Pressure ◽  
Vital Signs ◽  
Cardiovascular Responses ◽  
Energy Drinks ◽  
Energy Drink ◽  
Emergency Department Visits ◽  
Qtc Interval ◽  
Cardiac Responses ◽  
Energy Drink Consumption

Introduction: Energy drinks are presumed to enhance energy, physical endurance, mood, and boost metabolism. Serious health risks have been reported with energy drink consumption such as myocardial infarction, cardiac arrest, stroke, seizures, and arrhythmias. More than 20,000 emergency department visits related to energy drink consumption were reported in 2011. Little is known about the possible pathophysiological mechanisms and adverse events associated with energy drinks. Unlike the tobacco and alcohol industry, there are limited restrictions regulating the purchasing and marketing of these drinks. Purpose: To determine if consumption of energy drinks alter; vital signs (blood pressure, temperature), electrolytes (magnesium, potassium, calcium), activated bleeding time (ACT), or cardiac responses measured with a 12-lead electrocardiographic (ECG) Holter. Method: Subjects consumed two-16 ounce cans of an energy drink within one hour and remained in the lab where data was collected at base line (BL) and then during four hours post consumption (PC). Vital signs were taken every 30 minutes; blood samples were collected at BL, one, two and four hours PC and ECG data was collected throughout the entire study period. Paired students t-test and a corresponding non-parametric test (Wilcoxon signed rank) were used for analysis of the data. Results: Fourteen healthy young subjects were recruited (mean age 28.6 years). Systolic blood pressure (BL=132, ±7.83; PC= 151, ±11.21; p=.001); QTc interval (BL=423, ±22.74; PC=503, ±24.56; p<.001); magnesium level (BL 2.04, ± 0.09; PC=2.13, ±0.15; p=.05); and calcium level (BL=9.31, ±.28; PC=9.52, ±.22; p=.018) significantly increased from BL. While potassium and ACT fluctuated (increase and decrease) no significant changes were observed. Eight of the fourteen subjects (57%) developed a QTc >500 milliseconds PC. Conclusions: In our sample, consumption of energy drinks increased systolic blood pressure, serum magnesium and calcium, and resulted in repolarization abnormalities. Because these physiological responses can lead to arrhythmias and other abnormal cardiac responses, further study in a larger sample is needed to determine the effects and possible consequences of energy drink consumption.

scholarly journals Carotid and aortic baroreflexes of the rat: I. Open-loop steady-state properties and blood pressure variability

2000 ◽  
Vol 279 (5) ◽  
pp. R1910-R1921 ◽  
Author(s):  
Barry R. Dworkin ◽  
Susan Dworkin ◽  
Xiaorui Tang
Keyword(s):  
Blood Pressure ◽  
Venous Pressure ◽  
Open Loop ◽  
Direct Stimulation ◽  
Large Variability ◽  
Aortic Depressor Nerve ◽  
Cardiac Responses ◽  
C Fibers ◽  
Stimulus Mode ◽  
Sinus Pressure

To characterize the baroreflex in central nervous system-intact neuromuscular-blocked rats, we measured the vascular and cardiac responses and compared direct stimulation of the aortic depressor nerve (ADN) with a capacitance electrode (differentially activating either A or A + C fibers) to carotid sinus pressure with a micro-balloon (SINUS). One-thousand-two-hundred-ninety-seven open-loop measurements of systolic blood pressure (SBP), heart rate, venous pressure (VBP), and mesenteric (msBF), femoral (fmBF), and skin (skBF) blood flow were completed; the linear range of the effects was determined for each response and stimulus mode. The rats were sinoaortic denervated (SAD). The open-loop stimulation effect was very stable; e.g., the mean effect of 790 ADN stimulations during >7 days was −9.8 mmHg, with an average drift of +0.001 mmHg/h. In contrast, there was large variability of the SBP baseline (e.g., SD = ±10.9), which was due to SAD (±6.3 to ±16.3 mmHg, t = −13.9, df = 4, P < 0.0002) and was reversed by ganglionic block (±10.8 to ± 2.9 mmHg, t = −12.9, df = 3, P < 0.001). The ADN stimuli produced larger depressor responses than sinus stimuli (−66 vs. −45 mmHg); all component responses paralleled the magnitude of the SBP effect, except interbeat interval (IBI), for which the ADN ΔIBI was ≈10 times that of SINUS. For all stimuli, fmBF increased and msBF did not. Mesenteric and femoral vascular conductance both increased, whereas VBP decreased and skBF followed SBP. We found that for all baroreflex response components, with the exception of SINUS-elicited ΔIBI, there was an orderly, substantially linear, relationship between stimulus strength and response magnitude.

Cardiac responses to salinity variations in two differently zoned Mediterranean limpets

1999 ◽  
Vol 169 (7) ◽  
pp. 501-506 ◽  
Author(s):  
M. De Pirro ◽  
G. Santini ◽  
G. Chelazzi
Keyword(s):  
Cardiac Responses ◽  
Salinity Variations
Sign in / Sign up

Export Citation Format

Share Document