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Rapid force recovery in contracting skeletal muscle after brief ischemia is dependent on O2 availability
- Source :
- Journal of Applied Physiology. 87:2225-2229
- Publication Year :
- 1999
- Publisher :
- American Physiological Society, 1999.
-
Abstract
- We tested the hypothesis that contracting skeletal muscle can rapidly restore force development during reperfusion after brief total ischemia and that this rapid recovery depends on O2 availability and not an alternate factor related to blood flow. Isolated canine gastrocnemius muscle ( n = 5) was stimulated to contract tetanically (isometric contraction elicited by 8 V, 0.2-ms duration, 200-ms trains, at 50-Hz stimulation) every 2 s until steady-state conditions of muscle blood flow (controlled by pump perfusion) and developed force were attained (3 min). While maintaining the same stimulation pattern, muscle blood flow was then reduced to zero (complete ischemia) for 2 min. Normal blood flow was then restored to the contracting muscle; however, two distinct conditions of oxygenation (at the same blood flow) were sequentially imposed: deoxygenated blood (30 s), blood with normal arterial O2content (30 s), a return to deoxygenated blood (30 s), and finally a return to normal arterial O2 content (90 s). During the ischemic period, force development fell to 39 ± 6 (SE)% of normal (from 460 ± 40 to 170 ± 20 N/100 g). When muscle blood flow was restored to normal by perfusion with deoxygenated blood, developed force continued to decline to 140 ± 20 N/100 g. Muscle force rapidly recovered to 310 ± 30 N/100 g ( P < 0.05) during the 30 s in which the contracting muscle was perfused with oxygenated blood and then fell again to 180 ± 30 N/100 g when perfused with blood with low[Formula: see text]. These findings demonstrate that contracting skeletal muscle has the capacity for rapid recovery of force development during reperfusion after a short period of complete ischemia and that this recovery depends on O2availability and not an alternate factor related to blood flow restoration.
- Subjects :
- medicine.medical_specialty
Time Factors
Physiology
Partial Pressure
Ischemia
Biological Availability
Hemodynamics
In Vitro Techniques
Dogs
Physiology (medical)
Internal medicine
Carnivora
Animals
Medicine
Muscle, Skeletal
Total ischemia
biology
business.industry
Fissipedia
Skeletal muscle
Blood flow
Anatomy
biology.organism_classification
medicine.disease
Hindlimb
Oxygen
medicine.anatomical_structure
Cardiology
Female
medicine.symptom
business
Muscle Contraction
Muscle contraction
Subjects
Details
- ISSN :
- 15221601 and 87507587
- Volume :
- 87
- Database :
- OpenAIRE
- Journal :
- Journal of Applied Physiology
- Accession number :
- edsair.doi.dedup.....eecdc5df273586f8670de4a44e640f2c