Adrenaline and noradrenaline in human plasma during natural sleep

Abstract

Little is known at present about the physiology of sleep. The proximity of centres which probably control sleep and wakefulness with centres of autonomic activity suggests a functional connexion. We have therefore investigated the effect of natural sleep on the concentration of catechol amines in plasma. METHODSTwo or three blood samples were collected from each subject, the first during sleep, the second 5-10 min. later when the subject was awake and the third on the following morning before breakfast. The first sample was collected as follows: a sphygmomanometer cuff was tied round the subject's arm above the elbow when he went to bed. The cuff was rapidly inflated while he was asleep and, though this usually woke him, the arterial circulation of the forearm was arrested; a venous blood sample was taken without delay. With one exception, of which particular mention will be made, the first and second blood samples were collected between the hours of 11 p.m. and 3 a.m.; before inflating the cuff the investigator satisfied himself, by watching respiration and facial expression, that the subject was actually asleep at the time.Most subjects were voluntary patients suffering from psychoneurotic disorders, but in good physical health, capable ofrational behaviour and willing to co-operate. The purpose ofthe investigation and its experimental nature were fully explained to them. Some members of the nursing staff were also included in the series. Particular care was taken to have all sedative medication stopped during the 3 days preceding the experiment.Treatment of blood samples. Five ml. anticoagulant solution were mixed in a 20 ml. syringe with 15 ml. venous blood. In most experiments the fluoride-thiosulphate solution previously described (Weil-Malherbe & Bone, 1952) was used, but it was later replaced by a more nearly isotonic solution containing 1% (w/v) sodium ethylenediaminetetraacetate pH 7 0 (EDTA) and 2 % (w/v) sodium thiosulphate. Preliminary experiments had indicated that identical results were obtained when consecutive blood samples were collected from the same donor in the two solutions.The packed-cell volume of the diluted blood was determined on a small sample by centrifugation in Wintrobe tubes at 2000 g for 45 min. The rest of the sample was centrifuged at 1000 g for 15 min and the plasma removed by suction.Preparation of platelet-poor plasma and of platelet suspension. Blood (15 ml.) was collected in silicone-coated glass-stoppered test-tubes through serum needles (18 gauge x 11 in) mounted on a short length (approx. 7 cm) of' Portex' elastic drainage tubing, size 10 (Portland Plastics Ltd.). The test-tube contained 500 units of heparin (Boots Pure Drug Co.) in 0-1 ml. solution. The sample was centrifuged in silicone-coated centrifuge tubes, first at about 1000 g for 15 min, and again,

Dissociation of 24-hour catecholamine levels from blood pressure in older men.

“…Detailed, multiple sampling studies of 24-hour plasma levels of E and DA have not been previously reported, but a number of reports have suggested the existence of circadian rhythm of plasma and urinary £18, 19,22,24 T n e detectability of a diurnal rhythm of plasma E level in the aged and its obvious relation to the 24-hour cycle blood pressure levels suggest that at least some inherent chronobiological functions related to sympathetic outflow are preserved in the elderly. The reason for the dichotomy between the nocturnal decline in plasma E levels, MAP, and heart rate and the persistent high NE levels ( Figure 5) is not clear.…”

“…Urinary excretion of catecholamine metabolites has been observed to be higher during the day than at night. 16 " 19 Several investigative groups have reported a diurnal variation in plasma NE levels and noted a significant fall in NE levels during sleep in recumbent young normotensive 13 ' ' *• 2O " 22 and hypertensive subjects.…”

A Review of Psychoendocrine Research on the Sympathetic-Adrenal Medullary System

“…Virtually all the studies reported so far have involved urinary measurement of epinephrine and norepinephrine levels, although methods have been available for measuring plasma catecholamine levels for more than 10 years and were applied successfully to human studies as early as 1955 by Renton and Weil-Malherbe, who reported that plasma epinephrine levels were higher during the waking state than during sleep. 94 Several factors may account for this relative lack of studies of plasma catecholamine responses to psychological stimuli and this problem will be discussed in more detail later. An important factor in our own laboratory has been some early experimental observations on normal subjects in which 2 successive 25-ml.…”

Chronobiology of Blood Pressure

“…In addition, difficulties in the methods of collection, storage and measurement of the catecholamines in blood have led investigators to conclude that there is much 'noise', but no circadian variability in plasma norepinephrine [I], This is unlikely in light of the pronounced circadian rhythms found in epinephrine and norepinephrine by several other investigators, including Von Euler et at. [59], Cession-Fossion et al [ 12], Karkl [30], Petosse and Soulairac [46], Renton and Weil-Malherbe [51] and Reinberg et al [50], Reinberg et al compared the effects of (a) normal diurnal activity and regular uncontrolled diet with (b) complete 36-hour bed rest and a hypocaloric diet every 4 h. on urinary adrenaline (epinephrine) and nor adrenaline (norepinephrine), heart rate and blood pressure in normal healthy man. They found that the curves for adrenaline and noradrenaline closely paralleled those for pulse and blood pressure under both experimental condi tions.…”