Hemodynamic responses to mental stress during salt loading.

Purpose: The purpose was to examine whether prolonged moderate stress associated with a student exam would increase the blood pressure response to a salt load in young healthy normotensive individuals.

Methods: Ten healthy young subjects were examined at two different occasions in random order (i) during preparation for a medical exam (prolonged stress) and (ii) outside the exam period (low stress). All subjects consumed a controlled diet for 3 days with low- or high-salt content in randomized order.

Fluid shifts, vasodilatation and ambulatory blood pressure reduction during long duration spaceflight.

Key Points: Weightlessness in space induces initially an increase in stroke volume and cardiac output, accompanied by unchanged or slightly reduced blood pressure.It is unclear whether these changes persist throughout months of flight.Here, we show that cardiac output and stroke volume increase by 35–41% between 3 and 6 months on the International Space Station, which is more than during shorter flights.

Decrease in TSH Receptor Autoantibodies during Antithyroid Treatment: Relationship with a Long Noncoding Heg RNA and Cdk1 mRNA in Mononuclear Cells.

We have previously shown that a long noncoding RNA transcript Heg is negatively correlated with TSH receptor autoantibodies (TRAb) in patients with untreated Graves' disease and with CD14 mRNA in treated patients and controls. Thus patients with high concentrations of Heg RNA have low levels of TRAb or CD14 mRNA, respectively. Here we show that an additional factor, gene expression of Cdk1 in mononuclear cells, is positively related to concentrations of TRAb in patients with untreated Graves' disease.

Malignant pheochromocytomas and paragangliomas - the importance of a multidisciplinary approach.

Approximately 10% of the pheochromocytomas and 20% of the paragangliomas are malignant with poor survival. As the biological behaviour of these tumours cannot be predicted with certainty from pathology the diagnosis of malignancy is difficult. Genetic testing is gaining impact as mutations in the tumour suppressor gene Von Hippel-Lindau and the mitochondrial succinate dehydrogenase enzyme complex subunit B (SDHB) are associated with malignancy.

The paradox of systemic vasodilatation and sympathetic nervous stimulation in space.

Cardiac output is increased by some 18% by weightlessness during the initial week of spaceflight compared to upright standing or sitting on the ground and more so during the initial days of flight than at the end. In addition, mean 24-h diastolic, but not systolic pressure, is significantly decreased by 5mmHg. This is in accordance with observations that very acute weightlessness during parabolic airplane flights and a week of weightlessness in space leads to a decrease in systemic vascular resistance.

[Somatostatin analogues in the treatment of bleeding GI-angiodysplasias].

Angiodysplasias account for 2-8% of GI-bleeding episodes. We describe a 75-year-old patient with a history of anaemia for 1 year before being diagnosed with multiple angiodysplasias in the GI-tract. The patient needed weekly blood transfusions until he started treatment with octreotide.

Hemodynamic and neuroendocrine responses to changes in sodium intake in compensated heart failure.

Patients with untreated heart failure (HF) exhibit a blunted hemodynamic and neuroendocrine response to a high sodium intake, leading to excessive sodium and water retention. However, it is not known whether this is the case for patients with compensated HF receiving angiotensin-converting enzyme inhibitors and beta-adrenoreceptor blockers. Therefore, we determined the hemodynamic and neuroendocrine responses to 1 wk of a low-sodium diet (70 mmol/day) and 1 wk of a high-sodium diet (250 mmol/day) in 12 HF patients and 12 age-matched controls in a randomized, balanced fashion.

Vasorelaxation in space.

During everyday life, gravity constantly stresses the cardiovascular system in upright humans by diminishing venous return. This decreases cardiac output and induces systemic vasoconstriction to prevent blood pressure from falling. We therefore tested the hypothesis that entering weightlessness leads to a prompt increase in cardiac output and to systemic vasodilatation and that these effects persist for at least a week of weightlessness in space.

Acute effects of smoking on left ventricular function and neuro-humoral responses in patients with known or suspected ischaemic heart disease.

Systolic left ventricular function was examined by radionuclide ventriculography in 12 habitual smokers with known or suspected ischaemic heart disease, aged 33-69 years, before, during, and after smoking of two cigarettes in a row and was repeated on a non-smoking control day. Plasma concentrations of adrenaline, noradrenaline, renin, and angiotensin II were determined on the smoking day, before and immediately after smoking. During smoking, there were significant increases in heart rate (+27%), rate-pressure product (+23%), and cardiac output (+14%) in the face of a significant increase in left ventricular end-systolic volume (+5%) and significant decreases in ejection fraction (-6%) and stroke volume (-8%).

Elevated beta2-adrenoceptor protein concentration in adipose tissue from obese subjects is closely related to the body mass index and waist/hip ratio.

The aim of the present study was to quantify beta(2)-adrenoceptor protein content in adipose tissue during fasting, and to study the relationships between beta(2)-adrenoceptor protein and mRNA levels and changes in metabolites related to lipolysis. Groups of male subjects with a body mass index of <25 kg/m(2) or >30 kg/m(2) fasted for 60 h. Abdominal subcutaneous fat biopsies were analysed for receptor mRNA levels by reverse transcription-PCR-HPLC.

Tissue-specific response to interstitial angiotensin II in humans.

Angiotensin II is synthesized locally in various tissues; however, the role of interstitial angiotensin II in the regulation of regional metabolism and tissue perfusion is not clear. We characterized the effect of interstially applied angiotensin II in skeletal muscle and subcutaneous adipose tissue of young, normal-weight, healthy subjects by using the microdialysis technique. Furthermore, we tested the hypothesis that the effect of interstitial angiotensin II is modulated by nitric oxide.

Norepinephrine transporter function and autonomic control of metabolism.

Genetic variability, numerous medications, and some illicit drugs influence norepinephrine transporter (NET) function; however, the metabolic consequences of NET inhibition are poorly understood. We performed a randomized, double-blind, cross-over trial in 15 healthy subjects who ingested 8 mg of the selective NET inhibitor reboxetine or placebo. Energy expenditure and substrate oxidation rates were determined by indirect calorimetry before and during iv infusion of 0.

Effects of sodium intake on cardiovascular variables in humans during posture changes and ambulatory conditions.

The hypothesis was tested that cardiac output (CO) and stroke volume (SV) are increased by a moderate physiological elevation in sodium intake with a more pronounced effect in the ambulatory upright seated than supine position. Fourteen healthy males were investigated during ambulatory and controlled laboratory conditions at the end of two consecutive 5-day periods with sodium intakes of 70 (low) and 250 (high) mmol/24 h or vice versa, respectively. Comparing high and low sodium intake, plasma volume and plasma protein concentrations were 9 and 8% higher in the seated and the supine position, respectively.

Angiotensin II attenuates the natriuresis of water immersion in humans.

The hypothesis was tested that suppression of generation of ANG II is one of the mechanisms of the water immersion (WI)-induced natriuresis in humans. In one protocol, eight healthy young males were subjected to 3 h of 1) WI (WI + placebo), 2) WI combined with ANG II infusion of 0.5 ng.

Effects of supine, prone, and lateral positions on cardiovascular and renal variables in humans.

The hypothesis was tested that changing the direction of the transverse gravitational stress in horizontal humans modulates cardiovascular and renal variables. On different study days, 14 healthy males were placed for 6 h in either the horizontal supine or prone position following 3 h of being supine. Eight of the subjects were in addition investigated in the horizontal left lateral position.

Subcutaneous abdominal adipose tissue lipolysis during exercise determined by arteriovenous measurements in older women.

Objectives: To characterize the lipolytic response in the subcutaneous abdominal adipose tissue in older women to endurance exercise.

Design: Cross-sectional exercise study.

Setting: Exercise laboratory, Copenhagen, Denmark.

Comparison of acute cardiovascular responses to water immersion and head-down tilt in humans.

The hypothesis was tested that acute water immersion to the neck (WI) compared with 6 degrees head-down tilt (HDT) induces a more pronounced distension of the heart and lower plasma levels of vasoconstrictor hormones. Ten healthy males underwent 30 min of HDT, WI, and a seated control (randomized). During WI, left atrial diameter and stroke volume increased to the same extent as during HDT.