| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1Heart Institute (Instituto do Coração), Medical School, and 2School of Physical Education and Sports, University of São Paulo, São Paulo, Brazil; and 3Medical School, Department of Cardiology, University of California, Los Angeles, California
Submitted 21 December 2005 ; accepted in final form 16 June 2006
Exercise training improves arterial baroreflex control in heart failure (HF) rabbits. However, the mechanisms involved in the amelioration of baroreflex control are unknown. We tested the hypothesis that exercise training would increase the afferent aortic depressor nerve activity (AODN) sensitivity in ischemic-induced HF rats. Twenty ischemic-induced HF rats were divided into trained (n = 11) and untrained (n = 9) groups. Nine normal control rats were also studied. Power spectral analysis of pulse interval, systolic blood pressure, renal sympathetic nerve activity (RSNA), and AODN were analyzed by means of autoregressive parametric spectral and cross-spectral algorithms. Spontaneous baroreflex sensitivity of heart rate (HR) and RSNA were analyzed during spontaneous variation of systolic blood pressure. Left ventricular end-diastolic pressure was higher in HF rats compared with that in the normal control group (P = 0.0001). Trained HF rats had a peak oxygen uptake higher than untrained rats and similar to normal controls (P = 0.01). Trained HF rats had lower low-frequency [1.8 ± 0.2 vs. 14.6 ± 3 normalized units (nu), P = 0.0003] and higher high-frequency (97.9 ± 0.2 vs. 85.0 ± 3 nu, P = 0.0005) components of pulse interval than untrained rats. Trained HF rats had higher spontaneous baroreceptor sensitivity of HR (1.19 ± 0.2 vs. 0.51 ± 0.1 ms/mmHg, P = 0.003) and RSNA [2.69 ± 0.4 vs. 1.29 ± 0.3 arbitrary units (au)/mmHg, P = 0.04] than untrained rats. In HF rats, exercise training increased spontaneous AODN sensitivity toward normal levels (trained HF rats, 1,791 ± 215; untrained HF rats, 1,150 ± 158; and normal control rats, 2,064 ± 327 au/mmHg, P = 0.05). In conclusion, exercise training improves AODN sensitivity in HF rats.
baroreflex control; autonomic nervous system
This article has been cited by other articles:
|
|
 |
|
  I. H. Zucker, H. D. Schultz, K. P. Patel, W. Wang, and L. Gao Regulation of central angiotensin type 1 receptors and sympathetic outflow in heart failure Am J Physiol Heart Circ Physiol, November 1, 2009; 297(5): H1557 - H1566. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Komine, J. Sugawara, K. Hayashi, M. Yoshizawa, and T. Yokoi Regular endurance exercise in young men increases arterial baroreflex sensitivity through neural alteration of baroreflex arc J Appl Physiol, May 1, 2009; 106(5): 1499 - 1505. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Deley, G. Picard, and J. A. Taylor Arterial Baroreflex Control of Cardiac Vagal Outflow in Older Individuals Can Be Enhanced by Aerobic Exercise Training Hypertension, May 1, 2009; 53(5): 826 - 832. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. M. Mousa, D. Liu, K. G. Cornish, and I. H. Zucker Exercise training enhances baroreflex sensitivity by an angiotensin II-dependent mechanism in chronic heart failure J Appl Physiol, March 1, 2008; 104(3): 616 - 624. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Kanbar, V. Orea, B. Chapuis, C. Barres, and C. Julien A transfer function method for the continuous assessment of baroreflex control of renal sympathetic nerve activity in rats Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2007; 293(5): R1938 - R1946. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
