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Effect of caffeine ingestion on lymphocyte counts and subset activation in vivo following strenuous cycling.
Bishop, NC, Fitzgerald, C, Porter, PJ, Scanlon, GA, Smith, AC
European journal of applied physiology. 2005;(5-6):606-13
Abstract
Caffeine ingestion is associated with increases in the concentration of plasma epinephrine and epinephrine is associated with alterations in immune cell trafficking and function following intensive exercise. Therefore, the purpose of this study was to investigate the effect of caffeine ingestion on plasma epinephrine concentration, lymphocyte counts and subset activation in vivo, as measured by the expression the CD69 surface antigen, before and after intensive cycling. On two occasions, following an overnight fast and 60 h abstention from caffeine containing foods and drinks, eight endurance trained males cycled for 90 min at 70% O(2 max) 60 min after ingesting caffeine (6 mg kg(-1 )body mass; CAF) or placebo (PLA). Venous blood samples were collected at pre-treatment, pre-exercise, post-exercise and 1 h post-exercise. Plasma epinephrine concentrations were significantly higher in CAF compared with PLA at pre-exercise [0.28 (0.05) nmol l(-1) versus 0.08 (0.03) nmol l(-1), P<0.01; mean (SE)] and immediately post-exercise [1.02 (0.16) nmol l(-1) versuss 0.60 (0.13) nmol l(-1), P<0.01]. Compared with pre-treatment, numbers of CD4(+) and CD8(+) cells decreased by 54% and 55%, respectively, in CAF at 1 h post-exercise (both P<0.01) but did not significantly differ in PLA. Compared with PLA, in CAF the percentage of CD4(+)CD69(+) cells was 5-fold higher at post-exercise (P<0.05) and 5.5-fold higher at 1 h post-exercise (P=0.01). Compared with PLA, in CAF the percentage of CD8(+)CD69(+) cells was 2-fold higher at pre-exercise (P<0.05) and 1.7-fold higher at post-exercise (P<0.05). These findings suggest that caffeine ingestion is associated with alterations in lymphocyte subset trafficking and expression of CD69 in vivo following prolonged, intensive exercise.
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2.
Glucose ingestion blunts hormone-sensitive lipase activity in contracting human skeletal muscle.
Watt, MJ, Krustrup, P, Secher, NH, Saltin, B, Pedersen, BK, Febbraio, MA
American journal of physiology. Endocrinology and metabolism. 2004;(1):E144-50
Abstract
To examine the effect of attenuated epinephrine and elevated insulin on intramuscular hormone sensitivity lipase activity (HSLa) during exercise, seven men performed 120 min of semirecumbent cycling (60% peak pulmonary oxygen uptake) on two occasions while ingesting either 250 ml of a 6.4% carbohydrate (GLU) or sweet placebo (CON) beverage at the onset of, and at 15 min intervals throughout, exercise. Muscle biopsies obtained before and immediately after exercise were analyzed for HSLa. Blood samples were simultaneously obtained from a brachial artery and a femoral vein before and during exercise, and leg blood flow was measured by thermodilution in the femoral vein. Net leg glycerol and lactate release and net leg glucose and free fatty acid (FFA) uptake were calculated from these measures. Insulin and epinephrine were also measured in arterial blood before and throughout exercise. During GLU, insulin was elevated (120 min: CON, 11.4 +/- 2.4, GLU, 35.3 +/- 6.9 pM, P < 0.05) and epinephrine suppressed (120 min: CON, 6.1 +/- 2.5, GLU, 2.1 +/- 0.9 nM; P < 0.05) compared with CON. Carbohydrate feeding also resulted in suppressed (P < 0.05) HSLa relative to CON (120 min: CON, 1.71 +/- 0.18, GLU, 1.27 +/- 0.16 mmol.min-1.kg dry mass-1). There were no differences in leg lactate or glycerol release when trials were compared, but leg FFA uptake was lower (120 min: CON, 0.29 +/- 0.06, GLU, 0.82 +/- 0.09 mmol/min) and leg glucose uptake higher (120 min: CON, 3.16 +/- 0.59, GLU, 1.37 +/- 0.37 mmol/min) in GLU compared with CON. These results demonstrate that circulating insulin and epinephrine play a role in HSLa in contracting skeletal muscle.
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3.
Effect of alkalosis on plasma epinephrine responses to high intensity cycle exercise in humans.
Marx, JO, Gordon, SE, Vos, NH, Nindl, BC, Gómez, AL, Volek, JS, Pedro, J, Ratamess, N, Newton, RU, French, DN, et al
European journal of applied physiology. 2002;(1):72-7
Abstract
The purpose of this study was to determine the effects of alkalosis on epinephrine concentrations in response to a 90 s maximal exercise test. A group of ten healthy men ingested either a bicarbonate (BS) supplement (0.3 g x kg(-1) of body mass of sodium bicarbonate) or placebo mixture (P) prior to performing a 90 s maximal cycle ergometer test. An indwelling Teflon cannula was placed in the antecubital vein and blood samples were drawn at three times at rest separated by 10 min, immediately following the protocol, and at 2.5, 5, and 10 min post exercise to determine plasma epinephrine concentrations. Sodium bicarbonate ingestion significantly ( P<0.05) induced alkalosis both at rest [mean (SD) pH=7.42 (0.02) BS, 7.38 (0.02) P] and after the exercise protocol [pH=7.16 (0.02) BS, 7.12 (0.02) P]. Plasma epinephrine concentrations were not significantly different immediately post exercise between the two conditions [4.2 (0.6) compared to 4.2 (0.7) pmol x ml(-1) in BS and P, respectively]. Work performed and power output attained were not significantly different between the two treatment conditions [mean power=258.7 (35.1) W BS, 260.3 (35.4) W P; peak power=534.7 (61.6) W BS, 535.7 (54.4) W P]. The primary finding of this investigation was that orally-induced alkalosis does not significantly affect plasma epinephrine concentrations or performance following 90 s of maximal cycle exercise in untrained men.
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Vitamin C supplementation attenuates the increases in circulating cortisol, adrenaline and anti-inflammatory polypeptides following ultramarathon running.
Peters, EM, Anderson, R, Nieman, DC, Fickl, H, Jogessar, V
International journal of sports medicine. 2001;(7):537-43
Abstract
The effects of vitamin C supplementation on the alterations in the circulating concentrations of cortisol, adrenaline, interleukin-10 (IL-10) and interleukin-1 receptor antagonist (IL-1Ra) which accompany ultramarathon running were measured using immuno-chemiluminescence, radioimmunoassay and ELISA procedures. Forty-five participants in the 1999 Comrades 90 km marathon were divided into equal groups (n = 15) receiving 500 mg/day Vit C (VC-500), 1500 mg/day Vit C (VC-1500) or placebo (P) for 7 days before the race, on the day of the race, and for 2 days following completion. Runners recorded dietary intake before, during and after the race and provided 35 ml blood samples 15 - 18 hrs before the race, immediately post-race, 24 hrs post race and 48 hrs post-race. Twenty-nine runners (VC-1500, n = 12; VC-500, n = 10; P, n = 7) complied with all study requirements. All post-race concentrations were adjusted for plasma volume changes. Analyses of dietary intakes and blood glucose and anti-oxidant status on the day preceding the race and the day of the race did not reveal that carbohydrate intake or plasma vitamins E and A were significant confounders in the study. Mean pre-race concentrations of serum vitamin C in VC-500 and VC-1500 groups (128 +/- 31 and 153 +/- 34 micromol/l) were significantly higher than in the P group (83 +/- 39 micromol/l). Immediate post-race serum cortisol was significantly lower in the VC-1500 group (p < 0.05) than in P and VC-500 groups. When the data from VC-500 and P groups was combined (n = 17), immediate post-race plasma adrenaline, IL-10 and IL-1Ra concentrations were also significantly lower (p < 0.05) in the VC-1500 group. The study demonstrates an attenuation, albeit transient, of both the adrenal stress hormone and anti-inflammatory polypeptide response to prolonged exercise in runners who supplemented with 1500 mg vitamin C per day when compared to < or = 500 mg per day.
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5.
[Secretion of catecholamines in urine of patients with tonic-clonic epileptic seizures].
Kapustecki, J, Rościszewska, D, Pierzchała, K
Wiadomosci lekarskie (Warsaw, Poland : 1960). 2000;(9-10):499-506
Abstract
UNLABELLED Epileptic seizures are concerned with temporary neuronal activation of adrenal medulla, manifested by increase of adrenaline and noradrenaline concentration in plasma and clinical symptoms as, among others, an increase in blood pressure, tachycardia and temporary hyperglycaemia. This adrenergical activation may be probably due to reactivity changes in adrenal-sympathetic system in patients with epilepsy also in interseizure periods. AIM: Evaluation of adrenaline, noradrenaline and dopamine excretion in 24-hour period urine collection in epileptic patients and examination, if there is a correlation between epilepsy clinical picture and catecholamines urine elimination. MATERIAL 32 epileptic patients (16 women, 16 men) in mean age 31.1 +/- 7.1 and 29 healthy age-matched subjects in control. The age of falling ill, disease duration, etiology, family history, type and frequency of seizures, results of neurological and EEG examinations and the applied treatment, have all been taken into account in epilepsy clinical picture. METHOD Daily urine collection was performed on a day-off, and time lapse since the last epileptic seizure was at least 48 hours. Quantitative determination of adrenaline, noradrenaline and dopamine in urine was performed by fluorimetric method. Differences among the obtained values were compared by t-Student's test, additionally, correlation coefficient was calculated. RESULTS Significantly lower mean quantities of dopamine excreted within 24 hours in the whole group of epileptic patients and no significant differences in adrenaline and noradrenaline excretion were found, in relation to control group. Differences in catecholamines excretion in some cases occurred, in correlation with epilepsy clinical picture (onset of epilepsy, results of neurological and EEG examination, phenytoin treatment). CONCLUSIONS Obtained results suggest the reactivity disturbance of dopamine-noradrenaline-adrenaline system in the epilepsy course. It may result in changes of catecholamines, especially dopamine, excretion with urine.