Exercise Significantly Increases Plasma Adrenaline and Oxidized Low-Density Lipoprotein in Normal Healthy Subjects But Not in Persons With Spinal Cord Injury

Abstract

Mitsui T, Nakamura T, Ito T, Umemoto Y, Sakamoto K, Kinoshita T, Nakagawa M, Tajima F. Exercise significantly increases plasma adrenaline and oxidized low-density lipoprotein in normal healthy subjects but not in persons with spinal cord injury. ObjectivesTo compare plasma concentrations of oxidized low-density lipoprotein (oxLDL) and adrenaline during exercise between persons with spinal cord injury (SCI) and able-bodied (AB) individuals. DesignRandomized controlled study. SettingHuman laboratory at a medical university. ParticipantsPersons with SCI (n=7) and AB individuals (n=9). InterventionTwo-hour arm crank ergometer exercise at 60% maximum oxygen consumption. Main Outcome MeasuresPlasma oxLDL and adrenaline levels. ResultsExercise significantly increased plasma adrenaline levels in AB persons (mean ± SD: rest, 45.4±32.2pg/mL; exercise, 200.9±113.7pg/mL; P<.05) and persons with SCI; however; the magnitude of the increase in those with SCI was attenuated (mean ± SD: rest, 45.4±14.0pg/mL; exercise, 83.0±55.8pg/mL; P<.05). Exercise also significantly increased plasma oxLDL levels in AB persons (mean ± SD: rest, 102.2±30.2U/L; exercise, 179.7±60.0U/L; P<.05), but not in persons with SCI (mean ± SD: rest, 124.3±66.0U/L; exercise, 138.9±59.5U/L). ConclusionsThe results suggest that increases in plasma adrenaline levels during exercise contribute to the increase in plasma oxLDL levels.