Endogenous Agonist Regulation of α-Adrenoceptors in Man

1981 ◽  
Vol 61 (s7) ◽  
pp. 207s-210s ◽  
Author(s):  
I. B. Davies ◽  
D. Sudera ◽  
P. S. Sever
Keyword(s):  
Nervous System ◽  
Sympathetic Nervous System ◽  
Inverse Relationship ◽  
Normal Subjects ◽  
Plasma Noradrenaline ◽  
Adrenergic Agonist ◽  
Receptor Affinity ◽  
System Degeneration ◽  
Receptor Number ◽  
Sympathetic Nervous

1. Plasma noradrenaline concentrations and platelet α-receptor properties were measured in 14 normal subjects, five phaeochromocytoma patients and nine patients with multiple system atrophy and sympathetic nervous system degeneration (MSA). 2. Plasma noradrenaline concentrations in phaeochromocytoma were 10- to 20-times greater than those of normal subjects and one-fifth to one-half of normal in MSA patients. 3. Platelet α-receptor numbers were increased in MSA and decreased in phaeochromocytoma compared with normal subjects. There was no change in platelet α-receptor affinity in either group. 4. The inverse relationship between α-receptor numbers and plasma noradrenaline concentrations may reflect regulation of α-receptor number by endogenous adrenergic agonist concentrations in man.

Influence of the Sympathetic Nervous System on Aortic Compliance

1980 ◽  
Vol 59 (s6) ◽  
pp. 279s-282s ◽  
Author(s):  
C. L. Alicandri ◽  
R. Fariello ◽  
E. Agabiti-Rosei ◽  
G. Romanelli ◽  
G. Muiesan
Keyword(s):  
Nervous System ◽  
Sympathetic Nervous System ◽  
Stroke Volume ◽  
Pulse Pressure ◽  
Plasma Noradrenaline ◽  
Aortic Compliance ◽  
Sympathetic Nervous ◽  
Group 2 ◽  
Group 1 ◽  
Noradrenaline Levels

1. Aortic compliance and plasma catecholamine levels were determined in 26 essential hypertensive patients: 14<45 years (group 1) and 12>45 years (group 2). 2. Aortic rigidity, the reciprocal of aortic compliance, was calculated by the ratio of pulse pressure to stroke volume. Pulse pressure was derived by arterial pressure measured in the ascending aorta. Stroke volume was obtained by dye dilution. 3. A significant correlation (r = 0.60) was found between aortic rigidity and plasma noradrenaline in group 2. In this group both aortic rigidity and plasma noradrenaline levels were consistently higher than in group 1. 4. In 15 patients (seven of group 1 and eight of group 2) aortic rigidity was again measured after acute phentolamine (five patients) and labetalol (ten patients) administration. 5. Aortic rigidity was reduced significantly after both α-adrenoreceptor blockade alone and combined α- and β-adrenoreceptor blockade. A highly significant correlation was found between aortic rigidity reduction and pretreatment noradrenaline levels (r = 0.77). 6. Aortic compliance is influenced, at least in part, by sympathetic nervous system activity. Drugs which block the peripheral effects of catecholamines may improve aortic compliance and consequently the control of systolic hypertension in selected cases.

Relation of arterial pressure to spontaneous variations in digital volume

1960 ◽  
Vol 15 (1) ◽  
pp. 23-24 ◽  
Author(s):  
G. E. Burch ◽  
N. DePasquale
Keyword(s):  
Blood Pressure ◽  
Nervous System ◽  
Sympathetic Nervous System ◽  
Arterial Pressure ◽  
Blood Vessels ◽  
Arterial Blood Pressure ◽  
Peripheral Blood ◽  
Normal Subjects ◽  
Arterial Blood ◽  
Sympathetic Nervous

Simultaneous digital plethysmographic and brachial arterial pressure recordings in 11 normal subjects at rest in bed in a comfortable atmosphere showed that the spontaneous variations in digital volume (alpha and beta deflections) were independent of variations in arterial blood pressure. This indicates that the regulation of the caliber of the peripheral blood vessels as well as the spontaneous variations in the volume of the digital vessels is not passively produced by fluctuations in arterial blood pressure, including the Traube-Hering waves, but must be controlled by different centers and pathways of the sympathetic nervous system. Submitted on July 27, 1959

Plasma Dopamine β-Hydroxylase and Noradrenaline Amounts in Essential Hypertension

1973 ◽  
Vol 44 (6) ◽  
pp. 617-620 ◽  
Author(s):  
L. B. Geffen ◽  
R. A. Rush ◽  
W. J. Louis ◽  
A. E. Doyle
Keyword(s):  
Blood Pressure ◽  
Nervous System ◽  
Essential Hypertension ◽  
Sympathetic Nervous System ◽  
Diastolic Blood Pressure ◽  
Plasma Catecholamines ◽  
Plasma Noradrenaline ◽  
Elevated Blood Pressure ◽  
Elevated Blood ◽  
Sympathetic Nervous

1. Plasma dopamine β-hydroxylase (DβH) amounts were measured by radioimmunoassay in twenty-eight patients, twenty of whom had essential hypertension. There was a positive correlation between resting diastolic blood pressure and plasma DβH concentration. 2. Plasma DβH amounts also correlated significantly with those of plasma noradrenaline (NA) in individual patients. 3. These findings provide further support for the conclusions drawn from studies of plasma catecholamines that the sympathetic nervous system contributes toward the maintenance of the elevated blood pressure in essential hypertension.

scholarly journals Positive End-Expiratory Pressure Increases Plasma Catecholamine Levels in Non-Volume Loaded Dogs

1986 ◽  
Vol 14 (4) ◽  
pp. 421-425 ◽  
Author(s):  
B. Chernow ◽  
S. Soldano ◽  
D. Cook ◽  
P. Lyons ◽  
M. Barton ◽  
...  
Keyword(s):  
Nervous System ◽  
Sympathetic Nervous System ◽  
Water Pressure ◽  
Plasma Noradrenaline ◽  
Plasma Catecholamine ◽  
Sympathetic Nervous System Activity ◽  
Plasma Adrenaline ◽  
System Activity ◽  
Nervous System Activity ◽  
Sympathetic Nervous

Positive end-expiratory pressure (PEEP) is commonly used in the treatment of critically ill patients whose sympathetic nervous system is stressed; however, PEEP's actions on sympathetic nervous system activity are unknown. We therefore measured the plasma noradrenaline response (an index of sympathetic nervous system activity) to graded doses of PEEP in nine mongrel dogs. After 30 minutes at each level of PEEP, plasma noradrenaline concentrations increased from baseline mean values of 300 (SD 108) pg/ml to 388 (SD 225) pg/ml (P< 0.05) at 5 cm, 433 (SD 255) pg/ml (P <0.01) at 10 cm and 1194 (SD 882) pg/ml (P<0.01) at 20 cm water pressure of PEEP. The increases in plasma noradrenaline concentrations correlated inversely (r= - 0.43, P< 0.01) with PEEP-induced changes in cardiac output. Plasma adrenaline levels did not change significantly in response to 5 or 10 cm of PEEP; however, plasma adrenaline increased, while heart rate and mean arterial blood pressure fell, at 20 cm water pressure of PEEP (P < 0.05). Within 15 minutes after discontinuation of PEEP, the plasma catecholamine concentrations returned to baseline levels. Conclusions: 1. PEEP significantly increases sympathetic nervous system activity in a rapid, dose- dependent, reversible manner; 2. the PEEP-induced increases in sympathetic activity may explain the reductions in organ blood flow which others have observed following the initiation of PEEP; 3. PEEP-related changes in sympathetic nervous system activity are a consequence of PEEP- induced reductions in cardiac output.

Impaired Response of Plasma Renin Activity to Tilting after Renal Transplantation

1981 ◽  
Vol 61 (1) ◽  
pp. 69-73 ◽  
Author(s):  
J. Cunningham ◽  
M. J. Vandenburg ◽  
J. M. P. Holly ◽  
F. J. Goodwin
Keyword(s):  
Blood Pressure ◽  
Nervous System ◽  
Sympathetic Nervous System ◽  
Plasma Renin Activity ◽  
Pulse Rate ◽  
Dominant Role ◽  
Plasma Renin ◽  
Renin Activity ◽  
Plasma Noradrenaline ◽  
Sympathetic Nervous

1. Changes in plasma renin activity, plasma noradrenaline, pulse rate and blood pressure after tilting were measured in normal subjects and in patients with renal transplants. 2. There was a marked difference between the renin responses in the two groups, the increases in plasma renin activity in the control subjects being much greater than those in the transplanted patients. 3. Activation of the sympathetic nervous system after tilting, as indicated by changes in pulse rate, blood pressure and plasma noradrenaline, was similar in the two groups. 4. We conclude that the ability of the transplanted kidney to increase plasma renin activity after tilting is impaired, probably as a result of sympathetic denervation of the kidney during transplantation. The results suggest a dominant role of the sympathetic nervous system in the mediation of renin release after tilting.

Age-Dependence of Noradrenaline Kinetics in Normal Subjects

1981 ◽  
Vol 60 (2) ◽  
pp. 217-219 ◽  
Author(s):  
M. Esler ◽  
H. Skews ◽  
P. Leonard ◽  
G. Jackman ◽  
A. Bobik ◽  
...  
Keyword(s):  
Nervous System ◽  
Healthy Subjects ◽  
Plasma Clearance ◽  
Normal Subjects ◽  
Plasma Noradrenaline ◽  
Age Dependence ◽  
Plasma Noradrenaline Concentration ◽  
Noradrenaline Concentration ◽  
Sympathetic Nervous ◽  
Older Subjects

1. The influence of age on the rate of spillover of noradrenaline into plasma, clearance of noradrenaline from plasma, and plasma noradrenaline concentration at rest was studied in 34 healthy subjects aged 20–69 years. 2. The plasma concentration of noradrenaline was dependent on age, values being higher in older subjects. 3. This age-dependence of plasma noradrenaline concentration was due principally to a reduced clearance of noradrenaline from the circulation in older subjects. 4. The rate of spillover of noradrenaline into plasma was little influenced by age. The higher plasma noradrenaline values found in older subjects do not seem to be due to an increase in sympathetic nervous system tone with aging.

Effects of Oxygen Withdrawal on Catecholamine Release in Patients on Home Oxygen Therapy

1990 ◽  
Vol 79 (2) ◽  
pp. 155-159 ◽  
Author(s):  
M. S. Balter ◽  
K. R. Chapman ◽  
M. R. Maleki-Yazdi ◽  
F. H. H. Leenen ◽  
A. S. Rebuck
Keyword(s):  
Nervous System ◽  
Sympathetic Nervous System ◽  
Oxygen Therapy ◽  
Plasma Noradrenaline ◽  
Mental Function ◽  
Plasma Adrenaline ◽  
Sympathetic Nervous ◽  
Long Term Oxygen Therapy ◽  
Noradrenaline Levels

1. Long-term oxygen therapy in appropriate patients prolongs survival and corrects neuropsychological function. Some tests of mental function paradoxically improve during short periods of oxygen withdrawal in patients on long-term oxygen therapy, although the mechanism of this response is unknown. 2. To evaluate the effects of transient hypoxaemia on plasma adrenaline and noradrenaline levels, we studied eight oxygen-dependent patients who underwent either a 4 h period of oxygen withdrawal or their routine therapy, in a randomized, blinded fashion, on 2 separate days. 3. Plasma noradrenaline did not differ at baseline between study days. During normoxic conditions, plasma noradrenaline levels did not increase significantly with time. By contrast, under hypoxic conditions, plasma levels of noradrenaline rose significantly from 0 to 4 h (P < 0.05). The magnitude of the noradrenaline response was correlated with baseline noradrenaline such that subjects with the highest resting levels had the largest increase during hypoxia (r = 0.95, P < 0.001). 4. Plasma adrenaline did not differ at baseline between study days and there were no significant effects of hypoxia on plasma adrenaline levels. 5. We conclude that the sympathetic nervous system, but not the adrenal medulla, is stimulated in chronically oxygen-dependent subjects made acutely hypoxaemic. The magnitude of this stimulation appears to be related to the state of sympathetic nervous system activity at baseline. Improvement in some tests of mental function during transient periods of oxygen withdrawal may be due to non-specific arousal caused by a catecholamine surge.

Abstract 3036: Is the Sympathetic Nervous System, Renin-angiotensin System and Cytokines Activated in Asymptomatic Patients with Chronic Organic Mitral Regurgitation and Normal Left Ventricular Functional Reserve?

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Min Pu ◽  
William Davidson ◽  
Xiaoxue Fan ◽  
Lawrence Demers
Keyword(s):  
Nervous System ◽  
Sympathetic Nervous System ◽  
Mitral Regurgitation ◽  
Exercise Capacity ◽  
Normal Subjects ◽  
Lv Function ◽  
Functional Reserve ◽  
Post Exercise ◽  
Tnf Α ◽  
Sympathetic Nervous

Activation of the sympathetic nervous system, reninangiotensin system and cytokines has been observed in patients (pts) with congestive heart failure associated with chronic mitral regurgitation (MR). In order to further understand the pathophysiology of chronic MR, it is important to know whether these neurohormonal systems are activated in pts with chronic MR and normal LV function. Methods: Twenty pts with chronic MR were studied. All the pts had mitral valve prolapse and moderately severe or severe MR with a mean regurgitant orifice area of 0.42 ± 0.05 cm 2 . Mean exercise capacity on the Bruce protocol was 12 ± 3 Mets. LV diameters and LVEF were measured at rest and immediately post exercise by echocardiography. Normal LV function was defined as resting LV ejection fraction (LVEF) of > 60 % with normal LV systolic functional reserve (increased LVEF of ≥ 5% post exercise). Plasma norepinephrine (NP), renin activity (RA) and tumor necrosis factor-alpha (TNF-α) were measured in pts with MR and 13 normal subjects without MR. Results: LV end-diastolic diameter (5.4 ± 0.5 cm vs. 4.5 ± 0.5 cm, p<0.01) and end-systolic diameter (3.6 ± 0.6 cm vs. 2.6 ± 0.5 cm, p<0.01) were significantly larger in pts with MR than the normal subjects. Resting LVEF was similar in two groups (MR: 65 ± 4% vs. normal: 59 ± 6%, p>0.05). There were no significant differences in plasma NP, RA and TNF-α between the MR and normal groups (Table ). NP, RA and TNF-α were not significantly associated with exercise capacity, LV end-diastolic and systolic diameters and pre- and post-exercise LVEF (all p> 0.05). Conclusion: Unlike pts with LV dysfunction and MR, neurohormones are not significantly activated in asymptomatic pts with chronic MR and normal LV systolic functional reserve. Therefore, elevation of the neurohormonal levels and/or reduced LV functional reserve may indicate LV function impairment and prompt early surgical and/or medical intervention.

Plasma Noradrenaline and Renovascular Hypertension in the Rat

1976 ◽  
Vol 51 (s3) ◽  
pp. 439s-442s
Author(s):  
J. L. Reid ◽  
H. J. Dargie ◽  
S. S. Franklin ◽  
Beverly Fraser
Keyword(s):  
Nervous System ◽  
Sympathetic Nervous System ◽  
Renal Artery ◽  
Renovascular Hypertension ◽  
Plasma Noradrenaline ◽  
Hypertensive Rats ◽  
Contralateral Kidney ◽  
Sympathetic Nervous ◽  
Peripheral Sympathetic Nervous System

1. Plasma noradrenaline was measured in groups of rats up to 4 weeks after application of a renal artery clip. 2. When renal artery clipping was accompanied by contralateral nephrectomy (one-kidney model) plasma noradrenaline was significantly higher in hypertensive rats than in sham-operated control rats at 7, 14 and 28 days. 3. Plasma noradrenaline was not altered at any time examined in the two-kidney model (unilateral clip and contralateral kidney left in situ). 4. Neurogenic mechanisms mediated by the peripheral sympathetic nervous system appear to participate in the development of one-kidney renovascular hypertension, but do not play a significant role in the two-kidney model.

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