Variations in serum dopamine β-hydroxylase in normal subjects and chronic alcoholics

1978 ◽  
Vol 56 (5) ◽  
pp. 806-811 ◽  
Author(s):  
Edward M. Sellers ◽  
Stanley D. Cooper ◽  
Marie Lessard Roy

Serum dopamine β-hydroxylase (DBH) activity varies greatly between individuals but is usually relatively constant within individuals. DBH activity was determined in 20 normal subjects and 6 chronic alcoholics during alcohol ingestion and withdrawal, under controlled and standardized conditions. For all subjects mean random DBH was 423 ± 249 (mean ± SD) nmol phenylethanolamine/h per millilitre serum. Between-day serum DBH values vary more than within-day values (21.1% vs. 15.1%). Cold-pressor testing or sudden standing does not increase mean DBH; however, some individuals show a significant increase which cannot be elicited on repeat testing. Mean DBH activity did not vary significantly over 24 h. Clinically useful correlations between single random DBH and blood pressure or 24-h urine catechols should not be expected.

1993 ◽  
Vol 3 (5) ◽  
pp. 303-310 ◽  
Author(s):  
Frank Weise ◽  
Dominique Laude ◽  
Arlette Girard ◽  
Philippe Zitoun ◽  
Jean-Philippe Siché ◽  
...  

1964 ◽  
Vol 19 (6) ◽  
pp. 1145-1150 ◽  
Author(s):  
William R. Keatinge ◽  
Malcolm B. McIlroy ◽  
Alan Goldfien

A shower of ice-cold water (0@#X2013;2.5 C) over the chest caused large increases in systolic and diastolic arterial pressures, pulse pressure, and pulse rate in normal subjects. Cardiac output rose by 59 and 100% in the two subjects in whom it was measured. The changes in pressure were considerably larger than those caused by a cold pressor test or by anxiety. The changes appear to be due to sympathetic nervous reflexes to the heart and blood vessels rather than release of adrenal catecholamines, as plasma epinephrine did not increase and plasma norepinephrine rose only by 0.32 @#X00B5;g/liter. Hyperventilation and evidence of peripheral venoconstriction occurred during the showers, but neither voluntary hyperventilation nor increased venous return from a change in posture produced the changes in blood pressure seen during shower arterial blood pressure; cardiac output; catecholamines; sympathetic nervous reflexes; hyperventilation; peripheral venoconstriction Submitted on March 10, 1964


Hypertension ◽  
2000 ◽  
Vol 36 (suppl_1) ◽  
pp. 702-702
Author(s):  
Jens Jordan ◽  
Hakan Toka ◽  
Karsten Heusser ◽  
Okan Toka ◽  
John R Shannon ◽  
...  

P53 We have shown that autosomal-dominant hypertension with brachydactyly regularly features brainstem neurovascular compression (NVC). To seek mechanisms by which NVC could influence blood pressure, we conducted extensive autonomic tests in 5 affected persons (18-34 yrs.). Cold pressor testing, hand-grip testing, and upright posture all increased BP excessively. Baseline muscle sympathetic nerve activity was 15±4.6 bursts/min in patients, 12±6 bursts/min in normotensive controls, and 14±9 bursts/min in borderline hypertensive controls (ns). The increase in nerve traffic during cold pressor testing was not excessive. Urinary norepinephrine excretion was 19±4.0 μg/24 hours (normal range 23-105 μg/ 24 hours). Blood pressure during ganglionic blockade was134±4.9/ 82±4.1 mmHg in patients and 90±6/49±2.4 mmHg in controls (p<0.05). In patients, plasma vasopressin concentration changed from 0.47±0.03 pg/ml at baseline to 0.84±0.23 pg/ml during ganglionic blockade. In contrast, in control subjects, plasma vasopressin concentration increased profoundly from 1.6±0.17 pg/ml at baseline to 39±13 pg/ml during ganglionic blockade. The phenylephrine dose that increased SBP 12.5 mmHg was 8.0±2.0 μg in patients and 135±35 μg in control subjects before ganglionic blockade (p<0.01). During ganglionic blockade, the dose of phenylephrine that increased SBP 12.5 mmHg was 5.4±0.4 μg in patients and 13±4.8 μg in control subjects. The baroreflex slope was 9.4±1.6 msec/mmHg. We conclude that in these patients, basal BP was increased even during interruption of sympathetic and parasympathetic nerve traffic. However, sympathetic stimuli caused an excessive increase in BP. This excessive response cannot be explained by increased sympathetic nerve traffic or increased vascular sensitivity. Instead, we suggest that the ability of the baroreflex to buffer changes in blood pressure is severely impaired despite retained heart rate control.


1992 ◽  
Vol 19 (7) ◽  
pp. 481-488 ◽  
Author(s):  
Masatoshi Koshiji ◽  
Hiroyasu Ito ◽  
Shinya Minatoguchi ◽  
Hiroko Watanabe ◽  
Yoko Imai ◽  
...  

2000 ◽  
Vol 39 (02) ◽  
pp. 200-203
Author(s):  
H. Mizuta ◽  
K. Yana

Abstract:This paper proposes a method for decomposing heart rate fluctuations into background, respiratory and blood pressure oriented fluctuations. A signal cancellation scheme using the adaptive RLS algorithm has been introduced for canceling respiration and blood pressure oriented changes in the heart rate fluctuations. The computer simulation confirmed the validity of the proposed method. Then, heart rate fluctuations, instantaneous lung volume and blood pressure changes are simultaneously recorded from eight normal subjects aged 20-24 years. It was shown that after signal decomposition, the power spectrum of the heart rate showed a consistent monotonic 1/fa type pattern. The proposed method enables a clear interpretation of heart rate spectrum removing uncertain large individual variations due to the respiration and blood pressure change.


2020 ◽  
pp. 1-26
Author(s):  
Marie N Teisen ◽  
Stine Vuholm ◽  
Jesper M Rantanen ◽  
Jeppe H Christensen ◽  
Camilla T Damsgaard ◽  
...  

Abstract Long-chain n-3 PUFA (n-3 LCPUFA) have been shown to reduce blood pressure, heart rate and vagal tone, but potential stress-mitigating effects of n-3 LCPUFA are not well investigated. We aim to explore the effects of oily fish consumption on long-term stress and the stress response in schoolchildren. Healthy 8-9-year-old children were randomized to receive ~300 g/week of oily fish or poultry for 12 ± 2 weeks. At baseline and endpoint, we measured erythrocyte n-3 LCPUFA, hair cortisol and the response to a 1-min cold pressor test (CPT) on saliva cortisol, blood pressure, and continuous electrocardiogram recordings. Of the 199 randomized children, 197 completed the trial. Hair cortisol did not differ between the groups, but a sex-interaction was indicated (Psex*group = 0.074, difference between means -0.9 (95% CI: -2.9,1.0) ng/g and 0.7 (-0.2,1.6) ng/g in boys and girls, respectively). The children in the fish group tended to be less prone to terminate CPT prematurely (OR 0.20 [0.02,1.04]). The mean heart beat interval during CPT was 18.2 (0.3,36.6) ms longer and the high frequency power increased (159 (29,289) ms2) in the fish versus the poultry group. The cardiac autonomic response in the 10 min following CPT was characterized by a sympathetic peak followed by a parasympathetic peak, which was most pronounced in the fish group. This exploratory study does not support a strong effect of oily fish consumption on stress, but indicates that oily fish consumption may increase vagal cardiac tone during the physiological response to CPT. These results warrant further investigation.


1985 ◽  
Vol 69 (5) ◽  
pp. 533-540 ◽  
Author(s):  
Gianfranco Parati ◽  
Guido Pomidossi ◽  
Agustin Ramirez ◽  
Bruno Cesana ◽  
Giuseppe Mancia

1. In man evaluation of neural cardiovascular regulation makes use of a variety of tests which address the excitatory and reflex inhibitory neural influences that control circulation. Because interpretation of these tests is largely based on the magnitude of the elicited haemodynamic responses, their reproducibility in any given subject is critical. 2. In 39 subjects with continuous blood pressure (intra-arterial catheter) and heart rate monitoring we measured (i) the blood pressure and heart rate rises during hand-grip and cold-pressor test, (ii) the heart rate changes occurring during baroreceptor stimulation and deactivation by injection of phenylephrine and trinitroglycerine, and (iii) the heart rate and blood pressure changes occurring with alteration in carotid baroreceptor activity by a neck chamber. Each test was carefully standardized and performed at 30 min intervals for a total of six times in each subject. 3. The results showed that the responses to any test were clearly different from one another and that this occurred in all subjects studied. For the group as a whole the average response variability (coefficient of variation) ranged from 10.2% for the blood pressure response to carotid baroreceptor stimulation to 44.2% for the heart rate response to cold-pressor test. The variability of the responses was not related to basal blood pressure or heart rate, nor to the temporal sequence of the test performance. 4. Thus tests employed for studying neural cardiovascular control in man produce responses whose reproducibility is limited. This phenomenon may make it more difficult to define the response magnitude typical of each subject, as well as its comparison in different conditions and diseases.


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