Increase in plasma noradrenaline concentration after the administration of phentolamine in the patients with "latent" left-sided heart failure.

1. Changes in plasma noradrenaline levels and heart rate were used as measures of baroreflex sensitivity in six hypertensive subjects given serial incremental doses of sodium nitroprusside (intravenously) to lower blood pressure. 2. The rises in both heart rate and plasma noradrenaline concentration were linearly related to the decrement in blood pressure and inversely related to the severity of the hypertension. 3. A positive correlation between rise in heart rate and rise in plasma noradrenaline was found for each subject. With increasing severity of hypertension, a greater increase in heart rate occurred for each increment in plasma noradrenaline concentration. 4. Baroreflex sensitivity can be assessed by relating changes in heart rate to change in arterial pressure; however, this method does not distinguish the relative contributions of the vagal and sympathetic components of the autonomic neural response or variations in the chronotropic response to sympathetic stimulation. 5. Changes in plasma noradrenaline levels in response to graded reductions in blood pressure may be a more appropriate measure of baroreflex sensitivity than the methods currently used in clinical investigation.

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The effect of light exercise on the plasma superoxide dismutase activity and on the plasma noradrenaline concentration.

Industrial Health ◽

10.2486/indhealth.19.133 ◽

1981 ◽

Vol 19 (2) ◽

pp. 133-138 ◽

Cited By ~ 1

Author(s):

Masayasu MINAMI ◽

Kazuko MORI ◽

Toshiharu NAGATSU

Keyword(s):

Superoxide Dismutase ◽

Superoxide Dismutase Activity ◽

Plasma Noradrenaline ◽

Plasma Noradrenaline Concentration ◽

Noradrenaline Concentration ◽

Effect Of Light

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Determination of Noradrenaline Uptake, Spillover to Plasma and Plasma Concentration in Patients with Essential Hypertension

Clinical Science ◽

10.1042/cs059311s ◽

1980 ◽

Vol 59 (s6) ◽

pp. 311s-313s ◽

Cited By ~ 18

Author(s):

M. Esler ◽

G. Jackman ◽

P. Leonard ◽

A. Bobik ◽

Helen Skews ◽

...

Keyword(s):

Essential Hypertension ◽

Normal Subjects ◽

Plasma Noradrenaline ◽

Neuronal Uptake ◽

Noradrenaline Uptake ◽

Plasma Noradrenaline Concentration ◽

Noradrenaline Concentration ◽

Uptake Of Noradrenaline ◽

Rapid Removal ◽

Autonomic Insufficiency

1. The rates of entry of noradrenaline to plasma and of removal of noradrenaline from plasma, and plasma noradrenaline concentration, were determined in normal subjects and in patients with essential hypertension. Neuronal uptake of noradrenaline was assessed from the plasma tritiated noradrenaline disappearance curve, after infusion to steady state. 2. Noradrenaline disappearance was biexponential. Rapid removal was dependent on neuronal uptake, being slowed if neuronal noradrenaline uptake was reduced, either by desipramine in normal subjects, or in patients with sympathetic nerve dysfunction (autonomic insufficiency). 3. In 10 of 41 hypertensive patients the t1 1/2 similarly was prolonged, presumptive evidence of a defect in neuronal noradrenaline uptake. Endogenous noradrenaline escaping uptake after release, and spilling over into plasma, and plasma noradrenaline concentration, were increased in these patients. 4. Defective neuronal uptake of noradrenaline, by exposing adrenoreceptors to high local transmitter concentration, may be important in the pathogenesis of essential hypertension in some patients.

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Studies on the Mechanism of Mineralocorticoid-Induced Blood Pressure Increase in Man

Clinical Science ◽

10.1042/cs057303s ◽

1979 ◽

Vol 57 (s5) ◽

pp. 303s-305s ◽

Cited By ~ 16

Author(s):

A. Distler ◽

T. Philipp ◽

B. Lüth ◽

G. Wucherer

Keyword(s):

Blood Pressure ◽

Total Peripheral Resistance ◽

Peripheral Resistance ◽

Pressure Rise ◽

Sympathetic Tone ◽

Plasma Noradrenaline ◽

Steroid Administration ◽

Arterial Blood ◽

Plasma Noradrenaline Concentration ◽

Noradrenaline Concentration

1. To gain insight into the mechanism of mineralocorticoid-induced blood pressure rise in man we performed haemodynamic studies in six normotensive volunteer subjects before and during administration of the synthetic steroid 9α-fluorocortisol (0·8 mg daily) for a period of 6 weeks. In a further study, performed in seven subjects, plasma noradrenaline concentration and reactivity to exogenous noradrenaline were determined before and during administration of the mineralocorticoid. 2. Within the first week of steroid administration an increase in mean arterial blood pressure could be demonstrated, which was due to an increase in cardiac output. After the sixth week the elevated blood pressure was the consequence of an increased total peripheral resistance. 3. Plasma noradrenaline concentration decreased and reactivity to exogenous noradrenaline increased during steroid administration. 4. The mechanism underlying the increase in total peripheral resistance during long-term mineralocorticoid administration remains unclear. Increased sympathetic tone does not seem to be a factor since plasma noradrenaline decreased considerably. Pressor response to noradrenaline increased probably due to decreased sympathetic tone.

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