Central chemoreflex sensitivity and sympathetic neural outflow in elite breath-hold divers

被引:39
作者
Dujic, Zeljko [1 ]
Ivancev, Vladimir [1 ]
Heusser, Karsten [2 ,3 ]
Dzamonja, Gordan [4 ]
Palada, Ivan [1 ]
Valic, Zoran [1 ]
Tank, Jens [2 ,3 ]
Obad, Ante [1 ]
Bakovic, Darija [1 ]
Diedrich, Andre [5 ]
Joyner, Michael J. [6 ]
Jordan, Jens [2 ,3 ]
机构
[1] Univ Split, Sch Med, Dept Physiol, Split 21000, Croatia
[2] Charite Campus Buch, Franz Volhard Clin Res Ctr, Max Delbruck Ctr, Berlin, Germany
[3] HELIOS Klin, Berlin, Germany
[4] Clin Hosp Split, Dept Neurol, Split, Croatia
[5] Vanderbilt Univ, Autonom Dysfunct Serv, Nashville, TN USA
[6] Mayo Clin, Coll Med, Dept Anesthesiol, Rochester, NY USA
关键词
ultrasound; muscle sympathetic nerve activity; apnea; human;
D O I
10.1152/japplphysiol.00844.2007
中图分类号
Q4 [生理学];
学科分类号
071003 ;
摘要
Repeated hypoxemia in obstructive sleep apnea patients increases sympathetic activity, thereby promoting arterial hypertension. Elite breath-holding divers are exposed to similar apneic episodes and hypoxemia. We hypothesized that trained divers would have increased resting sympathetic activity and blood pressure, as well as an excessive sympathetic nervous system response to hypercapnia. We recruited 11 experienced divers and 9 control subjects. During the diving season preceding the study, divers participated in 7.3 +/- 1.2 diving fish-catching competitions and 76.4 +/- 14.6 apnea training sessions with the last apnea 3-5 days before testing. We monitored beat-by-beat blood pressure, heart rate, femoral artery blood flow, respiration, end-tidal CO2, and muscle sympathetic nerve activity (MSNA). After a baseline period, subjects began to rebreathe a hyperoxic gas mixture to raise end-tidal CO2 to 60 Torr. Baseline MSNA frequency was 31 +/- 11 bursts/min in divers and 33 +/- 13 bursts/min in control subjects. Total MSNA activity was 1.8 +/- 1.5 AU/min in divers and 1.8 +/- 1.3 AU/min in control subjects. Arterial oxygen saturation did not change during rebreathing, whereas end-tidal CO2 increased continuously. The slope of the hypercapnic ventilatory and MSNA response was similar in both groups. We conclude that repeated bouts of hypoxemia in elite, healthy breath-holding divers do not lead to sustained sympathetic activation or arterial hypertension. Repeated episodes of hypoxemia may not be sufficient to drive an increase in resting sympathetic activity in the absence of additional comorbidities.
引用
收藏
页码:205 / 211
页数:7
相关论文
共 35 条
[1]   CONTROL OF VENTILATION IN ELITE SYNCHRONIZED SWIMMERS [J].
BJURSTROM, RL ;
SCHOENE, RB .
JOURNAL OF APPLIED PHYSIOLOGY, 1987, 63 (03) :1019-1024
[2]   Interaction of chemoreceptor and baroreceptor reflexes by hypoxia and hypercapnia - a mechanism for promoting hypertension in obstructive sleep apnoea [J].
Cooper, VL ;
Pearson, SB ;
Bowker, CM ;
Elliott, MW ;
Hainsworth, R .
JOURNAL OF PHYSIOLOGY-LONDON, 2005, 568 (02) :677-687
[3]   Hypoxia-mediated prolonged elevation of sympathetic nerve activity after periods of intermittent hypoxic apnea [J].
Cutler, MJ ;
Swift, NM ;
Keller, DM ;
Wasmund, WL ;
Smith, ML .
JOURNAL OF APPLIED PHYSIOLOGY, 2004, 96 (02) :754-761
[4]  
DAVIS FM, 1987, UNDERSEA BIOMED RES, V14, P527
[5]   Ventilatory responses to hypercapnia in divers and non-divers: effects of posture and immersion [J].
Delapille, P ;
Verin, E ;
Tourny-Chollet, C ;
Pasquis, P .
EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY, 2001, 86 (01) :97-103
[6]   Extreme human breath-hold diving [J].
Ferretti, G .
EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY, 2001, 84 (04) :254-271
[7]   DYNAMIC RESPIRATORY RESPONSE TO ABRUPT CHANGE OF INSPIRED CO2 AT NORMAL AND HIGH PO2 [J].
GELFAND, R ;
LAMBERTSEN, CJ .
JOURNAL OF APPLIED PHYSIOLOGY, 1973, 35 (06) :903-913
[8]   Obstructive sleep apnea-dependent and -independent adrenergic activation in obesity [J].
Grassi, G ;
Facchini, A ;
Trevano, FQ ;
Dell'Oro, R ;
Arenare, F ;
Tana, F ;
Bolla, GB ;
Monzani, A ;
Robuschi, M ;
Mancia, G .
HYPERTENSION, 2005, 46 (02) :321-325
[9]   Chronic intermittent hypoxia increases sympathetic responsiveness to hypoxia and hypercapnia [J].
Greenberg, HE ;
Sica, A ;
Batson, D ;
Scharf, SM .
JOURNAL OF APPLIED PHYSIOLOGY, 1999, 86 (01) :298-305
[10]   Sympathetic neural overactivity in healthy humans after prolonged exposure to hypobaric hypoxia [J].
Hansen, J ;
Sander, M .
JOURNAL OF PHYSIOLOGY-LONDON, 2003, 546 (03) :921-929