Interstitial K⁺ in human skeletal muscle during and after dynamic graded exercise determined by microdialysis

TY - JOUR

T1 - Interstitial K+ in human skeletal muscle during and after dynamic graded exercise determined by microdialysis

AU - Juel, Carsten

AU - Pilegaard, Henriette

AU - Nielsen, Jens Jung

AU - Bangsbo, Jens

PY - 2000

Y1 - 2000

N2 - Interstitial K+ concentrations were measured during one-legged knee- extensor exercise by use of microdialysis with probes inserted in the vastus lateralis muscle of the subjects. K+ in the dialysate was measured either by flame photometry or a K+-sensitive electrode placed in the perfusion outlet. The correction for fractional K+ recovery was based on the assumption of identical fractional thallium loss. The interstitial K+ was 4.19 ± 0.09 mM at rest and increased to 6.17 ± 0.19, 7.48 ± 1.18, and 9.04 ± 0.74 mM at 10, 30, and 50 W exercise, respectively. The individual probes demonstrated large variations in interstitial K+, and values >10 mM were obtained. The observed interstitial K+, was markedly higher than previously found for venous K+, concentrations at similar work intensities. The present data support a potential role for interstitial K+, in regulation of blood flow and development of fatigue.

AB - Interstitial K+ concentrations were measured during one-legged knee- extensor exercise by use of microdialysis with probes inserted in the vastus lateralis muscle of the subjects. K+ in the dialysate was measured either by flame photometry or a K+-sensitive electrode placed in the perfusion outlet. The correction for fractional K+ recovery was based on the assumption of identical fractional thallium loss. The interstitial K+ was 4.19 ± 0.09 mM at rest and increased to 6.17 ± 0.19, 7.48 ± 1.18, and 9.04 ± 0.74 mM at 10, 30, and 50 W exercise, respectively. The individual probes demonstrated large variations in interstitial K+, and values >10 mM were obtained. The observed interstitial K+, was markedly higher than previously found for venous K+, concentrations at similar work intensities. The present data support a potential role for interstitial K+, in regulation of blood flow and development of fatigue.

KW - Fatigue

KW - Regulation of blood flow

UR - http://www.scopus.com/inward/record.url?scp=0034012317&partnerID=8YFLogxK

M3 - Journal article

C2 - 10666141

AN - SCOPUS:0034012317

SN - 0363-6119

VL - 278

SP - R400-R406

JO - American Journal of Physiology: Regulatory, Integrative and Comparative Physiology

JF - American Journal of Physiology: Regulatory, Integrative and Comparative Physiology

IS - 2

ER -