Plasma cyclic nucleotides and plasma catecholamines before and after prolonged treatment with clonidine in hypertensive patients

1981 ◽  
Vol 97 (3) ◽  
pp. 405-411 ◽  
Author(s):  
Per Manhem ◽  
Lise Heding ◽  
Jörgen Malmquist ◽  
Bernt Hökfelt

Abstract. The effect of standing and physical exercise on catecholamines and cyclic nucleotides in plasma was measured in 8 patients with essential hypertension under standardized conditions before and after prolonged treatment with clonidine. Before clonidine medication noradrenaline, adrenaline and cyclic AMP (cAMP) increased in response to standing and bicycling for 20 min. No significant correlation was found between their absolute levels nor was the increase in cAMP following exercise correlated to the increase in noradrenaline. Standing and physical exercise were without effect on cyclic GMP (cGMP). Clonidine reduced the plasma noradrenaline concentration in supine position and the noradrenaline and the adrenaline response to standing and exercise. Plasma cAMP was uneffected by clonidine under basal conditions but the response to exercise was slightly reduced initially. During clonidine there was a positive correlation between the plasma levels of cAMP and noradrenaline following work. Clonidine produced an increase in plasma cGMP in supine position, immediately prior to bicycling and after 5 min of exercise.

1998 ◽  
Vol 3 (4) ◽  
pp. 271-280 ◽  
Author(s):  
Hannah Steinberg ◽  
Briony R. Nicholls ◽  
Elizabeth A. Sykes ◽  
N. LeBoutillier ◽  
Nerina Ramlakhan ◽  
...  

Mood improvement immediately after a single bout of exercise is well documented, but less is known about successive and longer term effects. In a “real-life” field investigation, four kinds of exercise class (Beginners, Advanced, Body Funk and Callanetics) met once a week for up to 7 weeks. Before and after each class the members assessed how they felt by completing a questionnaire listing equal numbers of “positive” and “negative” mood words. Subjects who had attended at least five times were included in the analysis, which led to groups consisting of 18, 20, 16, and 16 subjects, respectively. All four kinds of exercise significantly increased positive and decreased negative feelings, and this result was surprisingly consistent in successive weeks. However, exercise seemed to have a much greater effect on positive than on negative moods. The favorable moods induced by each class seemed to have worn off by the following week, to be reinstated by the class itself. In the Callanetics class, positive mood also improved significantly over time. The Callanetics class involved “slower,” more demanding exercises, not always done to music. The Callanetics and Advanced classes also showed significantly greater preexercise negative moods in the first three sessions. However, these differences disappeared following exercise. Possibly, these two groups had become more “tolerant” to the mood-enhancing effects of physical exercise; this may be in part have been due to “exercise addiction.”


1980 ◽  
Vol 48 (1) ◽  
pp. 109-113 ◽  
Author(s):  
J. M. Pequignot ◽  
L. Peyrin ◽  
G. Peres

Adrenergic response to exercise and the relationships between plasma catecholamines and blood energetic substrates were studied in sedentary men after 15 h of fasting. Subjects pedaled a bicycle ergometer until exhaustion at a work load approximating 80% maximal oxygen consumption. Working ability was diminished by the fast (P less than 0.025). Resting plasma norepinephrine level was increased by fasting. During exercise plasma epinephrine (E) and norepinephrine (NE) concentrations were more elevated in fasting subjects than in fed subjects. Plasma catecholamine (CA) levels in fasting men correlated with blood glucose, blood lactate, and plasma glycerol concentrations. There was no significative correlation between CA and plasma free fatty acid (FFA) levels. The increased adrenergic activity in fasting subjects correlated with reduced endurance time. This study emphasizes the role of CA release, probably combined with other hormonal factors, in the mobilization of energy substrates during submaximal exercise.


Author(s):  
Valentina Bucciarelli ◽  
Francesco Bianco ◽  
Francesco Mucedola ◽  
Andrea Di Blasio ◽  
Pascal Izzicupo ◽  
...  

Background: Menopause is associated with negative cardiovascular adaptations related to estrogen depletion, which could be counteracted by physical exercise (PhE). However, the impact of total adherence-rate (TA) to PhE and sedentary time (SedT) on cardiometabolic profile in this population has not been elucidated. Methods: For 13-weeks, 43 women (57.1 ± 4.7 years) participated in a 4-days-a-week moderate-intensity walking training. They underwent laboratory, anthropometric and echocardiographic assessment, before and after training (T0–T1). Spontaneous physical activity (PhA) was assessed with a portable multisensory device. The sample was divided according to TA to PhE program: <70% (n = 17) and ≥70% (n = 26). Results: TA ≥ 70% group experienced a significant T1 improvement of relative wall thickness (RWT), diastolic function, VO2max, cortisol, cortisol/dehydroandrostenedione-sulphate ratio and serum glucose. After adjusting for SedT and 10-min bouts of spontaneous moderate-to-vigorous PhA, TA ≥ 70% showed the most significant absolute change of RWT and diastolic function, body mass index, weight and cortisol. TA ≥ 70% was major predictor of RWT and cortisol improvement. Conclusions: In a group of untrained, postmenopausal women, a high TA to a 13-weeks aerobic PhE program confers a better improvement in cardiometabolic profile, regardless of SedT and PhA levels.


1976 ◽  
Vol 41 (3) ◽  
pp. 383-387 ◽  
Author(s):  
D. L. Eckberg ◽  
F. M. Abboud ◽  
A. L. Mark

Carotid baroreceptors were stimulated with graded neck suction in supine and standing volunteers, before and after autonomic blockade, to determine the influence of posture on baroreflex responsiveness. Propranolol significantly augmented baroreflex pulse interval prolongation in the supine position. Upright posture did not modify baroreflex pulse interval responses prior to propranolol, but significantly augmented responses after propranolol. The results suggest that standing enhances baroreflex sensitivity, but that under normal circumstances, this effect is masked by beta-adrenergic stimulation. Augmentation of baroreflex pulse interval prolongation in the supine and standing positions by propranolol may contribute to the effectiveness of this drug in angina pectoris and labile hypertension.


1974 ◽  
Vol 63 (1) ◽  
pp. 213-222 ◽  
Author(s):  
JULIA C. BUCKINGHAM ◽  
J. R. HODGES

SUMMARY Changes in pituitary and plasma corticotrophin (ACTH), estimated by redox bioassay, were correlated with changes in plasma corticosterone in adrenalectomized rats, with and without corticosterone treatment, before and after exposure to stress. After adrenalectomy, the plasma ACTH concentration was persistently increased. The pituitary ACTH content declined and then increased markedly. These changes were prevented by physiological doses of corticosteroids. Stress caused only a small rise in the plasma ACTH concentration in intact and sham-operated rats but a marked increase in adrenalectomized animals. This exaggerated response was reduced to normal by physiological doses of corticosterone. Prolonged treatment with higher doses of corticosterone was necessary to abolish completely the adrenocorticotrophic response to stress. However, one injection of the steroid, in a dose sufficient to raise the plasma corticosterone concentration to a similar level, did not impair the stress-induced release of ACTH. The results suggest that the synthesis and the basal release of ACTH are directly controlled by the concentration of corticosteroid in the blood, but the corticosteroids exert only a delayed effect in modulating the stress-induced release of the hormone.


1965 ◽  
Vol 3 (9) ◽  
pp. 36-36

Fenfluramine (Ponderax - Selpharm) is a new appetite depressant, developed in France and introduced in Britain late in 1963. It is chemically related to amphetamine: its main distinguishing feature is a trifluoromethyl group attached to the benzene ring. The makers state that the drug does not stimulate the central nervous system, that it is not habit forming, and that it can be used by diabetics and hypertensive patients. They also state that it not only reduces the appetite, but also makes possible ‘prolonged treatment resulting in a true re-education of the appetite - which will persist after . . . ending . . . treatment’.


PEDIATRICS ◽  
2001 ◽  
Vol 108 (5) ◽  
pp. 1169-1174 ◽  
Author(s):  
John T. Kanegaye ◽  
Peyman Soliemanzadeh ◽  
John S. Bradley

Objective. Despite the lack of evidence defining a time interval during which cerebrospinal fluid (CSF) culture yield will not be affected by previous antibiotic therapy, recent publications cite a “minimum window” of 2 to 3 hours for recovery of bacterial pathogens after parenteral antibiotic administration. We conducted a retrospective review of children with bacterial meningitis to describe the rate at which parenteral antibiotic pretreatment sterilizes CSF cultures. Methods. The medical records of pediatric patients who were discharged from a tertiary children's hospital during a 5-year period with the final diagnosis of bacterial meningitis or suspected bacterial meningitis were reviewed. The decay in yield of CSF cultures over time was evaluated in patients with lumbar punctures (LP) delayed until after initiation of parenteral antibiotics and in patients with serial LPs before and after initiation of parenteral antibiotics. Results. The pathogens that infected the 128 study patients were Streptococcus pneumoniae (49),Neisseria meningitidis (37), group BStreptococcus (21), Haemophilus influenzae (8), other organisms (11), and undetermined (3). Thirty-nine patients (30%) had first LPs after initiation of parenteral antibiotics, and 55 (43%) had serial LPs before and after initiation of parenteral antibiotics. After ≥50 mg/kg of a third-generation cephalosporin, 3 of 9 LPs in meningococcal meningitis were sterile within 1 hour, occurring as early as 15 minutes, and all were sterile by 2 hours. With pneumococcal disease, the first negative CSF culture occurred at 4.3 hours, with 5 of 7 cultures negative from 4 to 10 hours after initiation of parenteral antibiotics. Reduced susceptibility to β-lactam antibiotics occurred in 11 of 46 pneumococcal isolates. Group B streptococcal cultures were positive through the first 8 hours after parenteral antibiotics. Blood cultures were positive in 74% of cases without pretreatment and in 57% to 68% of cases with negative CSF cultures. Conclusions. The temptation to initiate antimicrobial therapy may override the principle of obtaining adequate pretreatment culture material. The present study demonstrates that CSF sterilization may occur more rapidly after initiation of parenteral antibiotics than previously suggested, with complete sterilization of meningococcus within 2 hours and the beginning of sterilization of pneumococcus by 4 hours into therapy. Lack of adequate culture material may result in inability to tailor therapy to antimicrobial susceptibility or in unnecessarily prolonged treatment if the clinical presentation and laboratory data cannot exclude the possibility of bacterial meningitis.


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