Alkalosis and the plasma catecholamine response to high-intensity exercise in man.
OBJECTIVE
The aims of this study were to examine the plasma dopamine response to a controlled bout of short-duration high-intensity exercise and investigate the magnitude of the plasma dopamine (DA), norepinephrine (NE), and epinephrine (EPI) responses to this exercise after induced alkalosis.


METHODS
Eight male subjects were given in randomized order either; PLAC 0.3 g.kg(-1) body mass CaCO3 + 1 g NaCl, 0.3CIT 0.3 g.kg(-1) or 0.5CIT 0.5 g.kg(-1) body mass tri-sodium citrate in 500 mL water. One hour after ingestion subjects performed a 2-min cycle test at a workload calculated to elicit 110% VO(2max). Plasma catecholamines were measured using high performance liquid chromatography with electrochemical detection.


RESULTS
Antecubital venous blood pH and blood base excess (BBE) were significantly increased after ingestion of sodium citrate compared with placebo (P < 0.05). All postexercise sodium citrate blood pH and BBE values were significantly greater than placebo (P < 0.05). High-intensity exercise did not affect resting plasma DA concentrations. Peak plasma NE and EPI concentrations occurred immediately postexercise [NE PLAC 4.6 +/- 2.1 ES = 1.2, 0.3CIT 4.2 +/- 1.8 ES = 1.5, 0.5CIT 4.6 +/- 2.2 nmol.L(-1) ES = 1.2; EPI PLAC 0.6 +/- 0.3 ES = 1.3, 0.3CIT 0.5 +/- 0.2 ES = 1.3, 0.5CIT 0.5 +/- 0.3 nmol.L(-1) ES = 0.8] and were still elevated 5 min postexercise (P < 0.05). The magnitude of the plasma dopamine, norepinephrine and epinephrine response to exercise was unaltered with either 0.3CIT or 0.5CIT.


CONCLUSIONS
This study has demonstrated that performance of a controlled bout of high-intensity exercise did not alter the plasma dopamine concentration. In addition, alterations in blood alkalosis did not influence the magnitude of the plasma dopamine, norepinephrine or epinephrine responses to exercise.
Bracken
Richard M
RM
School of Science and the Environment, Coventry University, Priory St., Coventry, UK.
Linnane
Denise M
DM
Brooks
Stephen
S
D000136:Acid-Base Equilibrium; D000293:Adolescent; D000328:Adult; D000471:Alkalosis / Q000378:metabolism* / Q000503:physiopathology*; D015415:Biomarkers / Q000378:metabolism; D001794:Blood Pressure; D002395:Catecholamines / Q000097:blood / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D015444:Exercise; D006339:Heart Rate; D006801:Humans; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000097:blood; D008297:Male; D009200:Myocardial Contraction; D010953:Plasma Volume; D012123:Pulmonary Ventilation
D015415:Biomarkers; D002395:Catecholamines; D019344:Lactic Acid