title: Plasma free and sulfoconjugated catecholamine responses to varying exercise intensity.
abstract: Plasma free catecholamines rise during exercise, but sulfoconjugated catecholamines reportedly fall. This study examined the relationship between exercise intensity and circulating levels of sulfoconjugated norepinephrine, epinephrine, and dopamine. Seven exercise-trained men biked at approximately 30, 60, and 90% of their individual maximal oxygen consumption (VO2max) for 8 min. The 90% VO2max period resulted in significantly increased plasma free norepinephrine (rest, 219 +/- 85; exercise, 2,738 +/- 1,149 pg/ml; P less than or equal to 0.01) and epinephrine (rest, 49 +/- 49; exercise, 555 +/- 516 pg/ml; P less than or equal to 0.05). These changes were accompanied by consistent increases in sulfoconjugated norepinephrine at both the 60% (rest, 852 +/- 292; exercise, 1,431 +/- 639; P less than or equal to 0.05) and 90% (rest, 859 +/- 311; exercise, 2,223 +/- 1,015; P less than or equal to 0.05) VO2max periods. Plasma sulfoconjugated epinephrine and dopamine displayed erratic changes at the three exercise intensities. These findings suggest that sulfoconjugated norepinephrine rises during high-intensity exercise.
authors: Department of Human Kinetics, School of Allied Health Professions, University of Wisconsin-Milwaukee 53201.
authors: M S
authors: MS
authors: Sothmann
authors: A B
authors: AB
authors: Gustafson
authors: M
authors: M
authors: Chandler
mesh_terms: D000328:Adult; D002395:Catecholamines / Q000097:blood*; D004298:Dopamine / Q000031:analogs & derivatives / Q000097:blood*; D004837:Epinephrine / Q000031:analogs & derivatives* / Q000097:blood; D006801:Humans; D008297:Male; D009638:Norepinephrine / Q000031:analogs & derivatives* / Q000097:blood; D010101:Oxygen Consumption; D005082:Physical Exertion
chemical_list: D002395:Catecholamines; C036526:epinephrine sulfate; C017574:noradrenaline sulfate; D004298:Dopamine; D009638:Norepinephrine; D004837:Epinephrine