Myocardial and forearm blood flow reserve in mild-moderate essential hypertensive patients

1. Eleven untreated men with mild to moderate primary hypertension and 10 normotensive control subjects were studied at rest and during a mental stress test (Stroop colour word conflict test), which has previously been used in studies of hypertensive patients with regard to non-invasive cardiovascular variables and venous plasma catecholamine concentrations. 2. Heart rate, central cardiovascular pressures, cardiac output (thermodilution) and forearm blood flow (strain gauge plethysmography) were determined. Systemic and forearm vascular resistances were calculated. Arterial and venous plasma adrenaline and noradrenaline concentrations were measured by h.p.l.c., and arterial noradrenaline spillover and noradrenaline overflow from the forearm were assessed by isotope methodology ([3H]noradrenaline). Neuropeptide Y-like immunoreactivity was measured by radioimmunoassay. 3. In hypertensive patients heart rate, arterial blood pressure, cardiac output and forearm blood flow increased by 28%, 13%, 37% and 115%, respectively, and forearm and systemic vascular resistances decreased by 48% and 21%, respectively (P <0.001 for all responses), during stress. These responses were not different from those of the control group. 4. Arterial noradrenaline spillover rose by 63% and noradrenaline overflow from the forearm rose by 150% in the hypertensive patients in response to mental stress (P <0.001); no significant group differences could be demonstrated. However, the forearm noradrenaline overflow response to stress tended to be greater in the hypertensive group (P = 0.11). Arterial adrenaline concentrations doubled in both groups (P <0.001). 5. Arterial neuropeptide Y-like immunoreactivity increased slightly and similarly in the two groups (+7% in hypertensive patients and +9% in control subjects, P <0.05 for both) in response to mental stress. No net overflow of neuropeptide-Y-like immunoreactivity could be detected over the forearm. 6. It is concluded that the cardiovascular and sympatho-adrenal responses to mental stress evaluated in this study are similar in hypertensive patients and control subjects. Stress-induced vasodilatation occurs in the forearm despite signs of increased local sympathetic activity, indicating that powerful neurohormonal vasodilator mechanisms are activated by mental stress.

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The T-786C and Glu298Asp polymorphisms of the endothelial nitric oxide gene affect the forearm blood flow responses of Caucasian hypertensive patients

Journal of the American College of Cardiology ◽

10.1016/s0735-1097(02)03011-5 ◽

2003 ◽

Vol 41 (6) ◽

pp. 938-945 ◽

Cited By ~ 101

Author(s):

Gian Paolo Rossi ◽

Stefano Taddei ◽

Agostino Virdis ◽

Martina Cavallin ◽

Lorenzo Ghiadoni ◽

...

Keyword(s):

Nitric Oxide ◽

Blood Flow ◽

Forearm Blood Flow ◽

Hypertensive Patients ◽

Endothelial Nitric Oxide

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Coronary and forearm blood flow reserve in essential hypertension

American Journal of Hypertension ◽

10.1016/0895-7061(96)81522-6 ◽

1996 ◽

Vol 9 (4) ◽

pp. 24A ◽

Cited By ~ 1

Author(s):

R PEDRINELLI

Keyword(s):

Blood Flow ◽

Essential Hypertension ◽

Forearm Blood Flow ◽

Flow Reserve

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The effects of oral acebutolol and propranolol on forearm blood flow in hypertensive patients.

British Journal of Clinical Pharmacology ◽

10.1111/j.1365-2125.1981.tb01227.x ◽

1981 ◽

Vol 12 (3) ◽

pp. 363-368 ◽

Cited By ~ 22

Author(s):

MA Ireland ◽

WA Littler

Keyword(s):

Blood Flow ◽

Forearm Blood Flow ◽

Hypertensive Patients

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Forearm blood flow reserve and cardiac and renal indexes of pressure load in normotensive and hypertensive individuals.

Hypertension ◽

10.1161/01.hyp.24.1.24 ◽

1994 ◽

Vol 24 (1) ◽

pp. 24-29 ◽

Cited By ~ 10

Author(s):

R Pedrinelli ◽

G Catapano ◽

G Dell'Omo ◽

E Melillo ◽

L Talarico ◽

...

Keyword(s):

Blood Flow ◽

Forearm Blood Flow ◽

Pressure Load ◽

Flow Reserve

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The functional state of microcirculatory vessels in patients with arterial hypertension I-II degree with different degrees of cardiovascular risk

Systemic Hypertension ◽

10.26442/sg29017 ◽

2014 ◽

Vol 11 (2) ◽

pp. 29-35

Author(s):

E V Mordvinova ◽

E V Oschepkova ◽

A A Fedorovich ◽

A N Rogoza

Keyword(s):

Blood Flow ◽

Cardiovascular Risk ◽

Arterial Hypertension ◽

Progressive Increase ◽

Control Group ◽

Functional Tests ◽

Doppler Flowmetry ◽

Hypertensive Patients ◽

Flow Reserve ◽

Very High

Aim: to evaluate the main parameters of the microcirculatory blood flow and to determine its reserve capacity in patients with arterial hypertension (AH) and different degrees of cardiovascular risk (CVR).Subjects and methods. We examined 64 subjects aged 47-58 years, of which 27 were healthy volunteers and 37 patients with 1st and 2nd degree arterial hypertension, with medium, high and very high CVR (the antihypertensive therapy was cancelled for 2 weeks before the study). In all subjects laser Doppler flowmetry (LDF) with studing initial perfusion parameters, 2 constrictor and 3 dilatator tests waky perfomed. To assess the status of the tone-shaping «active» and «passive» parts of microcirculatory modulation, analysis of the amplitude and frequency spectrum of LDF- grams was carried out.Results. A significant increase in the rate of «base perfusion» in all hypertensive groups compared with the control group was found. The amplitude of respiratory oscillations was one-third higher in high and very high CVR groups in comparison with the control, the amplitude of the myogenic and neurogenic oscillations were maximal and reached significant values in very high CVR group. A reduction in constrictor response in hypertensive patients with middle and high CVR and its increase in the very high CVR group was shown during constrictor functional tests. The power of perfusion increase was reduced in response to all kinds of dilatator stimulus in hypertensive patients group.Conclusion. The findings indicate a progressive increase in the level of «base perfusion», worsening of venous congestion symptoms in hypertensive patients with the progression in CVR severity. High and very high CVR patients showed a reduction in myogenic tone of microvessels when compared with those with normotension. Dilatator functional tests showed a tendency to lower capillary blood flow reserve in hypertensive patients compared with the control group.

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Forearm vasoconstriction to endothelin-1 is impaired, but constriction to sarafotoxin 6c and vasodilatation to BQ-123 unaltered, in patients with essential hypertension

Clinical Science ◽

10.1042/cs103s053s ◽

2002 ◽

Vol 103 (s2002) ◽

pp. 53S-58S ◽

Cited By ~ 8

Author(s):

Charles J. FERRO ◽

William G. HAYNES ◽

Malcolm F. HAND ◽

David J. WEBB

Keyword(s):

Blood Pressure ◽

Blood Flow ◽

Essential Hypertension ◽

Receptor Agonist ◽

Forearm Blood Flow ◽

Hypertensive Patients ◽

Control Subjects ◽

Eta Receptor ◽

Etb Receptor ◽

And Control

The importance of endothelin-1 (ET-1) in the pathophysiology of essential hypertension is unclear. We therefore compared the effects of endothelin ETA receptor blockade and the stimulation of ETA and ETB receptors, and their interaction with the sympathetic nervous system, in the forearm resistance vessels of patients with essential hypertension and healthy control subjects. A total of 27 untreated patients with essential hypertension (blood pressure >160/100mmHg) and 25 normotensive (blood pressure <140/90mmHg) age- and sex-matched control subjects participated in these studies. A total of 10 patients and 10 controls took part in each phase. Locally active doses of study drugs were infused into the non-dominant brachial artery, while forearm blood flow was measured by venous occlusion plethysmography. A 60min infusion of BQ-123 (an ETA receptor antagonist; 100nmol/min) significantly increased forearm blood flow by 40±8% in hypertensive patients and by 35±5% in controls, with no difference between groups (P = 0.49). Forearm vasoconstriction to ET-1 (an ETA and ETB receptor agonist; 5 pmol/min) for 90min was significantly blunted in hypertensive patients (21±4%) compared with control subjects (37±3%; P = 0.0001). Forearm vasoconstriction to sarafotoxin S6c (an ETB receptor agonist; 10 pmol/min) for 90min was similar in hypertensive patients (44±5%) and control subjects (48±4%; P = 0.95). Sympathetically mediated vasoconstriction produced by lower-body negative pressure was not different in hypertensive patients compared with controls, and was not affected by infusion of ET-1 or sarafotoxin S6c. There were no differences in the observed increase in forearm blood flow with a control vasodilator (sodium nitroprusside) or the observed decrease in forearm blood flow with a control vasoconstrictor (noradrenaline) between hypertensive patients and control subjects. BQ-123 produced a significant increase in forearm blood flow in hypertensive patients, consistent with the anti-hypertensive actions of this agent. In conclusion, forearm vasoconstriction to ET-1, but not to sarafotoxin S6c, was reduced in patients with essential hypertension, consistent with possible down-regulation of the ETA receptor in this condition.

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