Impaired K+ regulation contributes to exercise limitation in end-stage renal failure
Sangkabutra, Termboon and Crankshaw, David P and Schneider, Claudia and Fraser, Steve F and Sostaric, Simon and Mason, Kim and Burge, Caroline M and Skinner, Sandford L and McMahon, Lawrence P and McKenna, Michael J (2003) Impaired K+ regulation contributes to exercise limitation in end-stage renal failure. Kidney international, 63 (1). pp. 283-290. ISSN 0085-2538Full text for this resource is not available from the Research Repository.
BACKGROUND: Patients with end-stage renal failure (ESRF) exhibit grossly impaired maximal exercise performance. This study investigated whether K+ regulation during exercise is impaired in ESRF and whether this is related to reduced exercise performance. METHODS: Nine stable hemodialysis patients and eight controls (CON) performed incremental cycling exercise to volitional fatigue, with measurement of peak oxygen consumption (VO2 peak). Arterial blood was sampled during and following exercise and analyzed for plasma [K+] (PK). RESULTS: The VO2 peak was approximately 44% less in ESRF than in CON (P < 0.001), whereas peak exercise PK was greater (7.23 +/- 0.38 vs. 6.23 +/- 0.14 mmol x L-1, respectively, P < 0.001). In ESRF, the rate of rise in PK during exercise was twofold greater (0.43 +/- 0.05 vs. 0.23 +/- 0.03 mmol. L-1x min-1, P < 0.005) and the ratio of rise in PK relative to work performed was 3.7-fold higher (90.1 +/- 13.5 vs. 24.7 +/- 3.3 nmol. L-1. J-1, P < 0.001). A strong inverse relationship was found between VO2 peak and the DeltaPK. work-1 ratio (r = -0.80, N = 17, P < 0.001). CONCLUSIONS: Patients with ESRF exhibit grossly impaired extrarenal K+ regulation during exercise, demonstrated by an excessive rise in PK relative to work performed. We further show that K+ regulation during exercise was correlated with aerobic exercise performance. These results suggest that disturbed K+ regulation in ESRF contributes to early muscle fatigue during exercise, thus causing reduced exercise performance.
|Uncontrolled Keywords:||exercise, kidney failure chronic metabolism, kidney failure chronic physiopathology, potassium blood, adult, exercise test, female, humans, kidney failure chronic therapy, male oxygen consumption, plasma volume, renal dialysis|
|Subjects:||RFCD Classification > 320000 Medical and Health Sciences
RFCD Classification > 330000 Education
Faculty/School/Research Centre/Department > Centre for Ageing, Rehabilitation, Exercise & Sport Science (CARES)
|Depositing User:||Ms Phung T Tran|
|Date Deposited:||22 Oct 2008 03:27|
|Last Modified:||16 Jun 2014 04:33|
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|Citations in Scopus:||15 - View on Scopus|
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