Relationship between plasma catecholamines and urinary catecholamine excretion rates in normal subjects and certain diseased states

Summary Relationships between plasma norepinephrine (PNE) or epinephrine (PE) and urinary norepinephrine (UNE) or epinephrine (UE) excretion rates were studied in 37 normal subjects, 39 patients with benign essential hypertension, 23 with unilateral renal hypertension, and 20 with bilateral renal disease (serum creatinine 2.3±2.6 mg/100 ml). Measurements were also performed after 6 weeks of diuretic treatment in 27 normal subjects and all patients with essential hypertension. In the untreated state, PNE and UNE values were generally normal in essential or unilateral renal hypertension; PNE tended to be decreased in diabetics and increased in bilateral renal disease. Diuretic treatment caused a tendency for slightly increased PNE and UNE. UNE correlated significantly with supine PNE or upright PNE or their mean value, and this relationship appeared to be comparable between untreated normal subjects and the various patient groups, except for a tendency for slightly higher PNE at given UNE values in bilateral renal disease. No significant correlations between UE and PE were apparent in the normal subjects or patient groups.These data demonstrate a dissociation of UE from PE levels. In contrast, UNE is an approximative index of PNE, and this relationship appeared to be generally unaltered in essential or unilateral renal hypertension. In patients with bilateral renal disease the slight shift of this relationship indicates that consideration of renal function is necessary for interpretation of NE levels.This study was supported by the Swiss National Science Foundation     

Effect of growth hormone on urinary excretion of catecholamines in man

Summary Administration of human growth hormone to 2 patients (severe growth retardation, operative panhypopituitarism) resulted in a significant reduction of the urinary excretion of adrenaline and tentatively increase of urinary excretion of noradrenaline.

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Zusammenfassung Zufuhr von menschlichen Wachstumshormon resultierte bei 2 Patienten (hypophysärer Zwergwuchs, operativ bedingter Panhypopituitarismus) in einer signifikanten Verminderung der Adrenalin-Ausscheidung und möglichem Anstieg der Noradrenalin-Ausscheidung.

     

Comparison of urinary and plasma catecholamine responses to mental stress

8 subjects were exposed to the Stroop mental performance test in a design with alternating hourly periods of rest and stress. During each period one urine sample and several venous plasma samples were obtained. Heart rate responded rapidly to initiation and termination of the stress exposure with increases and decreases respectively. Both urinary and plasma adrenaline increased significantly during stress. The plasma response was immediate and sustained. Neither urinary, nor plasma noradrenaline were significantly increased by the test. Plasma noradrenaline, however, increased significantly on termination of the exposure to stress. It was suggested that the latter effect may be due to muscle sympathetic nerve activity decreasing during stress and increasing following stress. The sample-to-sample variation was more than 20% of the mean for both catecholamines, indicating the need for frequent sampling to reliably reflect plasma levels. The mean intraindividual plasma/urine correlation was r?=0.70 (p<0.001) for adrenaline and r?=0.40 (p<0.05) for noradrenaline. When only resting periods were considered, no significant correlations remained, apparently due to a reduced range of variation and accompanying reduced signal-to-noise ratio. It is concluded that both urinary and plasma adrenaline may be useful in the evaluation of changes in sympatho-adrenal activity during stress.     

Comparison of cardiac versus vascular reactors and ethnic groups in plasma epinephrine and norepinephrine responses to stress

This study examined differences in plasma epinephrine (EPI) and norepinephrine (NOREPI) responses to stressors in 67 healthy African-American and Caucasian American men and women of the ages 18 to 49. Subjects were divided into three groups: (a) those who showed high blood pressure (BPI responses to stress associated with consistently high cardiac output (CO) increases with no substantial increases in total peripheral resistance (TPR), labeled cardiac reactors: (b) those with equally high BP increases associated with consistently higher TPR increases and lesser CO increases. labeled vascular reactors; (c) those who showed mixed hemodynamic responses or were low BP reactors. Ethnic and gender group differences in EPI and NOREPI responses were also examined. Cardiac reactors, vascular reactors and mixed + low reactors did not differ in EPI or NOREPI levels at baseline. During stressors, cardiac reactors showed greater increases in plasma EPI than vascular reactors or others during math, reaction time, and passive and active speech tasks: they also showed a weak trend toward greater NOREPI increases during these challenges as well. No differences were seen during the cold pressor: this stressor evoked the least change in EPI of all tasks, whereas the active speech elicited the greatest increases in both EPI and NOREPI of all tasks. Vascular reactors did not differ from mixed + low reactors in EPI or NOREPI reactivity, and men and women did not differ in EPI or NOREPI reactivity to any task. In contrast, Black subjects showed greater increases in NOREPI levels across all stressors compared to White subjects. These findings have implications for investigations of the role of sympathetic nervous system activity in the pathogenesis of hypertension in both African-American and Caucasian American populations.     

Longitudinal urinary creatinine excretion values among preadolescents and adolescents

To present longitudinal urinary creatinine excretion data for developmentally normal children 9-17 years of age. Only extremely limited data have been presented of a longitudinal nature for this age group. Overall, 507 children who participated in a prospective, randomized, controlled trial of dental materials safety were followed longitudinally for 7 years with renal measures, including creatinine excretion. Urinary creatinine means, confidence intervals, and 10th, 50th, and 90th percentiles are presented by year of age for the entire group, by sex, and by race (whites, blacks). Urinary creatinine excretion increases with age for both sexes and for both races (P<0.0001). No significant sexual difference were observed, although a race difference occurs, with blacks showing higher excretion levels than whites (P=0.0003). We present longitudinal urinary creatinine excretion data for ages 9-17 in which creatinine excretion increases with age throughout the time period. No sexual differences are observed, although blacks excrete significantly higher levels of urinary creatinine than do whites.     

Biogenic amines in anorexia nervosa: circadian rhythm in urinary excretion and influence of posture and physical task load on plasma catecholamines.

To investigate the sympathetic response in anorexia nervosa (AN) patients to stimuli occurring in normal life, biogenic amines were studied in 10 female outpatients. As control groups 10 lean and 10 normal weight healthy female subjects were included. It was hypothesized that the lean control group would have intermediate values between the AN patients and the normal weight controls. The AN patients and the lean controls had a mean underweight of 33.1% and 13.7%, respectively. For the excretion in 24-hr urine, differences among the groups were observed for several compounds, unexpectedly the values being lowest for the patients and highest for the lean controls. Furthermore, the lean controls had a higher excretion of a number of compounds in diurnal than in nocturnal urine, whereas this effect was absent or reversed for the AN patients and intermediate for the normal weight controls. Plasma norepinephrine was highest in the patients and lowest in the lean controls. The catecholamine response to postural changes and physical exercise did not differ among the groups. The results obtained indicate neither a (linear) relationship between underweight and the metabolism of biogenic amines nor a disturbed response to sympathetic stimulation in AN, but suggest an altered metabolism of biogenic amines in patients suffering from AN.     

实验性心肌肥厚大鼠血浆与心肌儿茶酚胺含量变化及黄芪的影响

结扎大鼠腹主动脉形成实验性心肌肥厚，对动物血浆及左心室组织中肾上腺素、去甲肾上腺素含量与心肌肥厚程度，以及黄芪注射液和卡托普利抗肥厚作用之间的相关性进行研究。手术4周后开始连续给药8周。以动物的心脏重量衡量心肌肥厚程度，用HPLC法测定血浆及左心室组织中肾上腺素和去甲肾上腺素含量，以SPSS统计软件对二者的相关性进行分析。结果显示模型组动物肾上腺素在血浆和心室组织中的含量均比对照组升高，去甲肾上腺素的血浆浓度比对照组升高，而其左心室组织中含量则低于对照组。黄芪注射液和卡托普利有不同程度的抗心肌肥厚作用，并可部分纠正肾上腺素和去甲肾上腺素含量的异常变化。相关性分析结果显示，心肌肥厚程度（全心重量、左心室重量）与左心室组织中去甲肾上腺素含量呈显著负相关性（P＜0．01）。上述结果提示：药物改变体内儿茶酚胺类物质含量可在一定程度上反映药物对心肌肥厚程度的影响。     

Orthostatic response of plasma renin activity and urinary kallikrein excretion in children with difficulty awakening in the morning

Twenty-six children, aged 10-15 years, with difficulty awakening in the morning, showed significantly lower plasma renin activity (PRA) before and after standing (15 and 60 min) and significantly greater postural fall in mean blood pressure than the age-matched control children. They also showed high urinary kallikrein excretion, but this was not statistically significant. These results suggest that low PRA and a readily decreasing blood pressure may contribute to difficulty awakening in the morning in teen-aged children.     

Increase of excretion of urinary catecholamines and its catabolites in a case of pulmonary sarcomatous tumor]

A five-year-old child presented with a large undifferentiated sarcoma in the right lung. Urinary catecholamines were assayed as tumor markers. A short-lived but significant rise in urinary norepinephrine and dopamine followed by rises in urinary levels of corresponding breakdown products were evidenced.     

Underestimation of cardiac vagal control in regular exercisers by 24-hour heart rate variability recordings

Objective

To examine whether ceiling effects at long inter beat intervals (IBIs)cause an underestimation of cardiac vagal control in regular exercisers by time and frequency-domain measures of respiratory sinus arrhythmia (RSA).

Methods

24-hour ECG and respiration recordings were performed in 26 regularly exercising subjects, actively engaged in aerobic training for the past year, and enrolled in supervised training in the six weeks pre-study, and in 26 age- and sex-matched non-exercisers. Sleep and waking levels of cardiac vagal control were estimated by RSA obtained through the peak-valley method, by the standard deviation of the IBIs, the root mean square of successive IBIs, and the high frequency IBI spectral power.

Results

In 11 of the exercisers the IBI-RSA relationship was characterized by a quadratic relationship. This reflected a ceiling effect at very long IBI values attained by regular exercisers, particularly during the nighttime recording. Irrespective of this ceiling effect, RSA as well as other heart rate variability (HRV) measures was still significantly larger in the exercisers with a quadratic IBI-RSA relationship than in non-exercisers or exercisers with a linear IBI-RSA relationship.

Conclusions

We conclude that a subgroup of regular exercisers is characterized by a low heart rate paired to high levels of cardiac vagal control. In these exercisers, vagal control is underestimated from HRV measures in ambulatory recordings. Inspection of the IBI-RSA relationship should be routinely added when HRV measures are used to index cardiac vagal control.