Related Experiment Videos
pH heterogeneity in skeletal muscle extracellular fluid
F Sjöberg1, P Thorborg, N Lund
1Department of Anesthesiology and Intensive Care, Faculty of Health Sciences, University Hospital, Linköping, Sweden.
International Journal of Microcirculation, Clinical and Experimental
|July 1, 1996
Summary
Skeletal muscle tissue pH (pHt) varies spatially in vivo, unlike previously assumed. This pH heterogeneity impacts cellular functions and is significantly influenced by carbon dioxide levels during hypercarbia.
Area of Science:
- Physiology
- Biochemistry
- Skeletal Muscle Research
Background:
- Oxygen and carbon dioxide exhibit heterogeneous distribution in tissues.
- Spatial variability of extracellular skeletal muscle tissue pH (pHt) is known in vitro but unexamined in vivo.
Purpose of the Study:
- To investigate in vivo pHt distributions in resting skeletal muscle.
- To determine the effect of pHt dispersion on ischemia and normoxic hypercarbia.
Main Methods:
- Utilized a multichannel pH microelectrode in an animal model.
- Measured local pHt under resting conditions, during induced ischemia, and normoxic hypercarbia.
Main Results:
- Resting skeletal muscle exhibited a pHt range of 6.96-7.68, with a maximum difference of 0.32 pH units between channels.
- Ischemia did not significantly alter local pHt differences.
- Normoxic hypercarbia caused a 2-fold increase in pHt variability (p < 0.01), indicating CO2 and blood buffering influence.
Conclusions:
- In vivo skeletal muscle pHt is heterogeneous, comparable to in vitro findings.
- Carbon dioxide and blood buffering significantly affect pHt distribution.
- Localized pHt variations can differentially impact cellular functions like H+ extrusion and membrane potential.