Catecholamine response to exercise in individuals with different levels of paraplegia

The purpose of this study was to investigate the effect of the level of injury on the serum level of norepinephrine (Nor) and epinephrine (Epi) at rest and after maximal exercise in individuals with paraplegia. Twenty-six male spinal cord-injured subjects with complete paraplegia for at least 9 months were divided into two groups of 13 subjects each according to the level of injury, i.e., T1-T6 and T7-T12. Serum Nor and Epi concentrations were measured by HPLC-ECD, at rest (PRE) and immediately after a maximal ergospirometric test (POST). Statistical analysis was performed using parametric and non-parametric tests. Maximal heart rate, peak oxygen uptake, and PRE and POST Nor were lower in the T1-T6 than in the T7-T12 group (166 Ý 28 vs 188 Ý 10 bpm; 18.0 Ý 6.0 vs 25.8 Ý 4.1 ml kg-1 min-1; 0.54 Ý 0.26 vs 0.99 Ý 0.47 nM; 1.48 Ý 1.65 vs 3.07 Ý 1.44 nM). Both groups presented a significant increase in Nor level after exercise, while only the T7-T12 group showed a significant increase in Epi after exercise (T1-T6: 0.98 Ý 0.72 vs 1.11 Ý 1.19 nM; T7-T12: 1.24 Ý 1.02 vs 1.89 Ý 1.57 nM). These data show that individuals with paraplegia above T6 have an attentuated catecholamine release at rest and response to exercise as compared to subjects with injuries below T6, which might prevent a better exercise performance in the former group

Neuromodulin (GAP-43): a protein related to chronic diseases

The important of a large number of proteins involved in chronic diseases has been reported. In the present study the phosphoprotein GAP-43 was focused due to its relationship with chronic diseases such as epilepsy Alzheimer's disease, cerebral ischemia and phusiological events like long-term potentiation (LTP).

Effect of an aerobic exercise program on blood pressure and catecholamines in normotensive and hypertensive subjects

Interrelations between physical exercise, monoamines and hypertension are postulated by various investigators. The purpose of the present study was to determine and compare catecholamine levels at rest and after a 12-week aerobic exercise program in 11 sedentary normotensive (N) and 8 hypertensive (H) men. Plasma catecholamines were determined by high performance liquid chromatography with electrochemical detection. A significant post-exercise increase in plasma noradrenaline was observed in the N and H groups (P<0.01) both before and after the aerobic exercise program. The hypertensive group showed a significant reduction of the sum of 7 skinfold thickness scores after the aerobic exercise program (from 178.7 ñ 65.6 to 144.0 ñ 47.4 mm) although no significant difference was observed when the body mass index was compared. A significant reduction in diastolic blood pressure at rest was observed in the H group after the aerobic exercise program (from 99.2 ñ 2.0 to 85.0 ñ 5.5). There were no significant differences in catecholamine concentrations between groups before and after the 12-week aerobic exercise program at rest and post-exercise. These data show a relationship between physical exercise and hypertension that was not related to changes in plasma catecholamine levels.

Serotonina sérica e síndrome de Rett / Serum serotonin and Rett syndrome

A síndrome de Rett, uma patologia neurodegenerativa que afeta meninas, caracteriza-se por uma involuçäo neuropsicomotora do desenvolvimento. Sendo o diagnóstico desta síndrome exclusivamente clínico, o presente trabalho teve como objetivo o estudo do conteúdo de serotonina sérica em crianças normais e portadoras da síndrome de Rett. A metodologia empregada para a quantificaçäo de 5HT no soro foi a cromatografia líquida de alta eficiência acoplada a detecçao eletroquímica. Os resultados obtidos mostraram uma hiperserotonemia em 81 por cento das crianças com síndrome de Rett. Verificou-se também uma correlaçäo positiva entre níveis altos de serotonina no soro e a deambulaçäo independente, mostrando que pacientes sem marcha voluntária apresentam níveis séricos maiores deste neurotransmissor. O presente trabalho sugere que o nível sérico de serotonina pode vir a ser usado como um possível marcador biológico no diagnóstico de estadiamento da síndrome de Rett.

Increased serotonin levels in physically trained men

It has been postulated that exercise training influences monoaminergic systems. The purpose of the present study was to determine the basal level of serum serotonin (5HT) in track and field-trained men (N = 15) and in untrained subjects matched by age, weight and height (N = 15). Serum serotonin levels were determined in blood drawn into dry tubes after a 12-h fast by high performance liquid chromatography utilizing electrochemical detection. Mean (+/- SD) serum serotonin levels were: 141.32 +/- 38.77 ng/ml for trained subjects and 97.77 +/- 30.53 ng/ml for untrained subjects (P < 0.01, Student t-test). These data show that basal serum serotonin levels are increased by exercise training.

Serum serotonin levels of normal and autistic children

1. Serum serotonin (5HT) was determined in normal and autistic children by high performance liquid chromatography with electrochemical detection (HPLC-ED), after serum deproteinization. 2. The sample deproteinization was carried out by the addition of 3.4 M HCLO4 to a small volume of the serum, followed by freezing, centrifugation, dilution and injection of sample into the HPLC. 3. Serum 5HT concentration was significantly increased in autistic children (303 +/- 92 ng/ml) (N = 19) when compared to that of normal children (215 +/- 67 ng/ml) (N = 46). The data of normal children analyzed by ANOVA for sex or age showed no difference. 4. The method employed in this study showed high resolution, good sensitivity and can be used for routine determination of serum 5HT in the clinical investigation of hyperserotonemia in autism