TY - JOUR

T1 - The uremic environment and muscle dysfunction in man and rat

AU - Harrison, Adrian Paul

AU - Nielsen, Arne Høj

AU - Eidemak, I.

AU - Molsted, S.

AU - Bartels, E.M.

PY - 2006

Y1 - 2006

N2 - Background: Patients reaching end-stage renal disease experience debilitating fatigue, with progression of this disease, rendering patients dysfunctional in their everyday lives. Methods: In vivo measurements of muscle function, assessed using surface electromyography (EMG), were made on 25 patients prior to and after a session of hemodialysis (HD) treatment, alongside in vitro measurements of muscle function in isolated rat muscles incubated in normal or uremic conditions approximating to those found in uremic rats (rat uremic: RU) or uremic humans (human uremic: HU). Results: HD significantly affected plasma values, e.g. reducing urea (69%), creatinine (62%), potassium (23%) and phosphate (48%) concentrations in patients (all p<0.01). Treatment also improved the EMG frequency of 2nd dorsal interosseous (fast-twitch) (p<0.01), although no change was noted for vastus lateralis (slow-twitch). In isolated rat muscles, a uremic environment had no significant effect on slow-twitch soleus during field stimulation, however, in fast-twitch extensor digitorum longus, a significant 23% (RU) and 22% (HU) faster rate of decline in force was measured, compared to controls (p<0.001 and p<0.01, respectively). Conclusion: It is concluded that (1) muscle weakness and its electrophysiological correlates may be rapidly induced by uremic solutes and rapidly reversed when the solutes are removed by dialysis, and (2) fast-twitch muscles are more readily affected by uremic conditions than slow-twitch muscles.

AB - Background: Patients reaching end-stage renal disease experience debilitating fatigue, with progression of this disease, rendering patients dysfunctional in their everyday lives. Methods: In vivo measurements of muscle function, assessed using surface electromyography (EMG), were made on 25 patients prior to and after a session of hemodialysis (HD) treatment, alongside in vitro measurements of muscle function in isolated rat muscles incubated in normal or uremic conditions approximating to those found in uremic rats (rat uremic: RU) or uremic humans (human uremic: HU). Results: HD significantly affected plasma values, e.g. reducing urea (69%), creatinine (62%), potassium (23%) and phosphate (48%) concentrations in patients (all p<0.01). Treatment also improved the EMG frequency of 2nd dorsal interosseous (fast-twitch) (p<0.01), although no change was noted for vastus lateralis (slow-twitch). In isolated rat muscles, a uremic environment had no significant effect on slow-twitch soleus during field stimulation, however, in fast-twitch extensor digitorum longus, a significant 23% (RU) and 22% (HU) faster rate of decline in force was measured, compared to controls (p<0.001 and p<0.01, respectively). Conclusion: It is concluded that (1) muscle weakness and its electrophysiological correlates may be rapidly induced by uremic solutes and rapidly reversed when the solutes are removed by dialysis, and (2) fast-twitch muscles are more readily affected by uremic conditions than slow-twitch muscles.

KW - Former LIFE faculty

KW - Uremia

KW - Muscle dysfunction

KW - Dyalysis

KW - Electromyography

KW - Muscle strength

U2 - 10.1159/000090221

DO - 10.1159/000090221

M3 - Journal article

C2 - 16352915

VL - 103

SP - 33

EP - 42

JO - Nephron - Clinical Practice

JF - Nephron - Clinical Practice

SN - 1660-8151

IS - 1

ER -