Metabolic correlates of fatigue and of recovery from fatigue in single frog muscle fibers
Author
dc.contributor.author
Nassar-Gentina, V.
Author
dc.contributor.author
Passonneau, J. V.
Author
dc.contributor.author
Vergara, J. L.
Author
dc.contributor.author
Rapoport, S. I.
Admission date
dc.date.accessioned
2019-01-29T15:46:05Z
Available date
dc.date.available
2019-01-29T15:46:05Z
Publication date
dc.date.issued
1978
Cita de ítem
dc.identifier.citation
Journal of General Physiology, Volumen 72, Issue 5, 2018, Pages 593-606
Identifier
dc.identifier.issn
15407748
Identifier
dc.identifier.issn
00221295
Identifier
dc.identifier.other
10.1085/jgp.72.5.593
Identifier
dc.identifier.uri
https://repositorio.uchile.cl/handle/2250/162326
Abstract
dc.description.abstract
Fatigue and recovery from fatigue were related to metabolism in single fibers of the frog semitendinosus muscle. The fibers were held at a sarcomere length of 2.3 µm in oxygenated Ringer solution at 15°C and were stimulated for up to 150 s by a schedule of 10-s, 20-Hz tetanic trains that were interrupted by 1-s rest periods, after which they were rapidly frozen for biochemical analysis. Two kinds of fatigue were produced in relation to stimulus duration. A rapidly reversed fatigue occurred with stimulation for under 40 s and was evidenced by a decline in tetanic tension that could be overcome by 1 s of rest. A prolonged fatigue was caused by stimulation for 100-150 s. It was evidenced during stimulation by a fall in tetanic tension that could not be overcome by 1 s of rest, and after stimulation by a reduction, lasting for up to 82 min, in the peak tension of a 200-ms test tetanus. Fiber phosphocreatine (PCr) fell logarithmically in relation to stimulus duration, from a mean of 121 ± 8