Effect of cholinergic blockade on heart rate, blood pressure and plasma catecholamine responses to mental stress in normal subjects

The contribution of epinephrine (Epi) to forearm vasodilator responses to mental stress was evaluated in 12 healthy men by comparing hemodynamic and plasma catecholamine responses to mental stress and to intravenous and intra-arterial infusions of epinephrine. Mental stress decreased forearm vascular resistance (FVR) by 45%, increased arterial Epi from 0.23 to 0.44 nmol/l in arterial plasma, and increased forearm norepinephrine overflow. Intra-arterial Epi infusion decreased FVR concentration dependently by up to 43%. Intravenous Epi infusion decreased diastolic arterial pressure and increased heart rate and systolic blood pressure dose dependently. FVR decreased by up to 39% at 4.60 nmol/l Epi in arterial plasma. The average Epi contribution to forearm vasodilation during mental stress was calculated to be between 9 and 30%, depending on if responses to stress were compared with intravenous or intra-arterial Epi infusion. Arterial atrial natriuretic peptide immunoreactivity increased by 23% during stress, supporting a vasodilator influence, whereas vasopressin immunoreactivity was unaffected. Thus secretion of Epi explains only part of the stress-induced forearm vasodilation. Intravenous infusion of Epi appears to activate sympathetic counterregulation.

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Heart Rate Signal Decomposition

Methods of Information in Medicine ◽

10.1055/s-0038-1634264 ◽

2000 ◽

Vol 39 (02) ◽

pp. 200-203

Author(s):

H. Mizuta ◽

K. Yana

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Pressure Change ◽

Normal Subjects ◽

Signal Decomposition ◽

Large Individual ◽

Heart Rate Fluctuations ◽

Type Pattern ◽

Signal Cancellation ◽

Pressure Changes

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.

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Haemodynamic responses to psychosocial stress during the menstrual cycle

Clinical Science ◽

10.1042/cs0810017 ◽

1991 ◽

Vol 81 (1) ◽

pp. 17-22 ◽

Cited By ~ 21

Author(s):

Karin Manhem ◽

Christina Jern ◽

Martin Pilhall ◽

Guy Shanks ◽

Sverker Jern

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Menstrual Cycle ◽

Systolic Blood Pressure ◽

Psychosocial Stress ◽

Mental Stress ◽

Luteal Phase ◽

Follicular Phase ◽

Two Phases ◽

Plasma Catecholamine Concentrations

1. The haemodynamic effects of hormonal changes during the menstrual cycle were examined in 11 normotensive women (age 20–46 years). The subjects were studied on days 2–8 (follicular phase) and days 18–26 (luteal phase) in a randomized order. A standardized mental stress test and a 24 h recording of ambulatory blood pressure and heart rate were performed. 2. Pre-stress resting levels of heart rate and blood pressure were similar during the two phases of the menstrual cycle. 3. During mental stress, the heart rate response was significantly greater during the luteal phase than during the follicular phase (14.7 versus 9.7 beats/min; P < 0.05). 4. Blood pressure, plasma catecholamine concentrations and subjective stress experience increased significantly in response to stress, without any significant differences between the two phases. 5. During 24 h ambulatory monitoring, higher levels of systolic blood pressure and heart rate were observed in the luteal phase than in the follicular phase (P < 0.005 and P < 0.0001, respectively). 6. These data indicate that cyclic variations in female sex hormones not only affect systolic blood pressure and heart rate, but also alter the haemodynamic responses to psychosocial stress.

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Postprandial changes in supine and erect heart rate, systemic blood pressure and plasma noradrenaline and renin activity in normal subjects

European Journal of Clinical Pharmacology ◽

10.1007/bf00637672 ◽

1987 ◽

Vol 32 (5) ◽

pp. 471-476 ◽

Cited By ~ 15

Author(s):

C. de Mey ◽

D. Enterling ◽

E. Brendel ◽

I. Meineke

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Normal Subjects ◽

Systemic Blood Pressure ◽

Renin Activity ◽

Plasma Noradrenaline ◽

Systemic Blood

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Cardiovascular and norepinephrine responses of men and women to two cold pressor tests

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y92-006 ◽

1992 ◽

Vol 70 (1) ◽

pp. 36-42 ◽

Cited By ~ 24

Author(s):

J. K. McLean ◽

P. Sathasivam ◽

K. MacNaughton ◽

T. E. Graham

Keyword(s):

Blood Pressure ◽

Gender Differences ◽

Heart Rate ◽

Latin Square ◽

Cold Pressor ◽

Plasma Norepinephrine ◽

Plasma Catecholamine ◽

The Face ◽

Blood Pressure Responses ◽

Venous Plasma

Two types of cold pressor tests were used to study gender differences in cardiovascular and plasma catecholamine responses. Ten male and ten female, young, healthy Caucasian subjects participated. The tests consisted of (1) 5 °C air blown at 3.5–4 m/s onto part of the face for 4 min and (2) the open right hand immersed to the wrist in water at 5 °C for 4 min. Heart rate, blood pressure (BP), and venous plasma norepinephrine were collected before, during, and 5 min after the 4 min of cold exposures. Test order was decided by a Latin square design, and the subjects rested in a quiet room for 30 min between the two tests. All parameters demonstrated significant (p < 0.01) increases from rest during the cold tests. Gender differences were significant (p < 0.01) in diastolic and systolic BP in each test with the males having a greater response, but gender differences were not found in heart rate or norepinephrine concentration. The study demonstrated that gender differences exist in the blood pressure responses to local cold, but that the mechanisms involved do not include a parallel difference in heart rate or venous plasma norepinephrine concentration.Key words: blood pressure, gender differences, stroke volume.

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Effects of the cold pressor test on short-term fluctuations of finger arterial blood pressure and heart rate in normal subjects

Clinical Autonomic Research ◽

10.1007/bf01827331 ◽

1993 ◽

Vol 3 (5) ◽

pp. 303-310 ◽

Cited By ~ 39

Author(s):

Frank Weise ◽

Dominique Laude ◽

Arlette Girard ◽

Philippe Zitoun ◽

Jean-Philippe Siché ◽

...

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Arterial Blood Pressure ◽

Cold Pressor Test ◽

Cold Pressor ◽

Normal Subjects ◽

Short Term ◽

Pressor Test ◽

Arterial Blood

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γ-l-Glutamyl-l-Dopa is a Dopamine Pro-Drug, Relatively Specific for the Kidney in Normal Subjects

Clinical Science ◽

10.1042/cs0690207 ◽

1985 ◽

Vol 69 (2) ◽

pp. 207-214 ◽

Cited By ~ 44

Author(s):

D. P. Worth ◽

J. N. Harvey ◽

J. Brown ◽

M. R. Lee

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Glomerular Filtration Rate ◽

Plasma Renin Activity ◽

Filtration Rate ◽

Renal Plasma Flow ◽

Plasma Renin ◽

Normal Subjects ◽

Urinary Sodium Excretion ◽

Systemic Effects

1. γ-l-Glutamyl-l-dopa was given by intravenous infusion to eight normal subjects at doses of 12.5 and 100 μg min−1 kg−1. 2. Both doses of the dipeptide resulted in an increase in mean urinary sodium excretion. 3. Mean effective renal plasma flow rose at both doses, but mean glomerular filtration rate increased only at the lower dose. 4. There was a fall in mean plasma renin activity after the infusion of both 12.5 and 100 μg min−1kg−1. 5. Mean urine free dopamine excretion increased by 280- and 2500-fold at infusion rates of 12.5 and 100 μg min−1 kg−1 respectively. 6. Mean plasma free dopamine rose at both doses but the increase at 12.5 μg min−1 kg−1 was not to a level previously associated with systemic effects of the catecholamine. 7. On administration of the dipeptide at 12.5 μg min−1 kg−1 there were no changes in blood pressure or heart rate, but at the higher dose there was a fall in diastolic blood pressure. 8. At a dose of 12.5 μg min−1 kg−1 in man, there is kidney specific conversion of gludopa to dopamine.

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Effects of Daily Intake of Almonds on Cardiac Autonomic Functions Measured by Heart Rate Variability in Response to Acute Stress: A Randomized Controlled Trial

Current Developments in Nutrition ◽

10.1093/cdn/nzaa040_020 ◽

2020 ◽

Vol 4 (Supplement_2) ◽

pp. 20-20

Author(s):

Vita Dikariyanto ◽

Leanne Smith ◽

May Robertson ◽

Eslem Kusaslan ◽

Molly O'Callaghan-Latham ◽

...

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Heart Rate Variability ◽

Mental Stress ◽

Autonomic Function ◽

Acute Stress ◽

Physical Stress ◽

Cardiometabolic Health ◽

Cardiac Autonomic Function ◽

Randomized Controlled

Abstract Objectives Stress is inversely associated with heart rate variability (HRV), an indicator of cardiac autonomic function and a predictor of risk of sudden cardiac death. At times of stress, people tend to favor high sugar and fatty foods, often as snacks, with potential adverse effects on cardiometabolic health. Dietary recommendations for cardiovascular disease (CVD) prevention emphasize fruits, vegetables, wholegrains and nuts. There is evidence that consumption of nuts can reduce LDL cholesterol and blood pressure and help with weight management, however the impact of nuts on HRV in response to stress is unknown. The ATTIS dietary intervention study investigated the HRV response to acute stress following 6-week substitution of almonds for typical snacks high in refined starch, free sugars and saturated fats, and low in fibre. The study population comprised adults aged 30–70 y, who were habitual snack consumers, and at moderate risk of developing CVD. It was hypothesized that snacking on almonds would increase HRV during stress tasks, when HRV is expected to be reduced due to increased sympathetic activity. Methods A 6-week randomized controlled parallel trial was conducted. Participants were randomized to 1) control snacks (mini-muffins formulated to follow the average UK snack nutrient profile), or 2) dry-roasted whole almonds, both providing 20% estimated energy requirement. Supine HRV was measured (Mega Electronics Emotion Faros 180°, 2-leads wearable ECG-HRV monitor) during resting (5 min), physical stress (blood pressure monitor cuff inflation 200 mmHg, 5 min) and mental stress (Stroop colour-word test, 5 min) tasks pre- and post-intervention. A total of 105 participants (73 females and 32 males; mean age 56.2 y, SD 10.4) completed the trial. Results Almonds significantly increased the beat-to-beat HRV parameter, high-frequency power, during the mental stress test (mean difference 124 ms2; 95% CI 11, 237; P = 0.031) relative to control, indicating increased parasympathetic regulation. There were no treatment effects during resting and the physical stress task. Conclusions Snacking on whole almonds as a replacement for typical snacks increases HRV during mental stress, indicating an increased resilience in cardiac autonomic function and a novel mechanism whereby nuts may be cardioprotective. Funding Sources Almond Board of California.

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Acupuncture effects on reflex responses to mental stress in humans

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.2001.280.5.r1462 ◽

2001 ◽

Vol 280 (5) ◽

pp. R1462-R1468 ◽

Cited By ~ 36

Author(s):

Holly R. Middlekauff ◽

Jun Liang Yu ◽

Kakit Hui

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Mental Stress ◽

Animal Studies ◽

Muscle Sympathetic Nerve Activity ◽

Real Acupuncture ◽

Normal Humans ◽

Needle Acupuncture

In animal studies, acupuncture has been shown to be sympathoinhibitory, but it is unknown if acupuncture is sympathoinhibitory in humans. Nineteen healthy volunteers underwent mental stress testing pre- and postacupuncture. Muscle sympathetic nerve activity (MSNA), blood pressure, and heart rate during mental stress were compared pre- and postacupuncture. Control acupuncture consisted of acupuncture at nonacupoints and “no-needle” acupuncture. Acupuncture had no effect on resting MSNA, blood pressure, or heart rate. After real acupuncture, the increase in mean arterial pressure (pre- vs. postacupuncture 4.5 vs. 1.7 mmHg, P < 0.001), but not MSNA or heart rate, was blunted during mental stress. Similarly, following nonacupoint acupuncture, the increase in mean arterial pressure was blunted during mental stress (5.4 vs. 2.9 mmHg, P < 0.0003). No-needle acupuncture had no effect on these variables. In conclusion, acupuncture at traditional acupoints, nonacupoints, and no-needle acupuncture does not modulate baseline MSNA or MSNA responses to mental stress in normal humans. Acupuncture significantly attenuates the increase in blood pressure during mental stress. Needling nonacupoints, but not “no-needle” acupuncture, have a similar effect on blood pressure.

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