Interaction between series compliance and sarcomere kinetics determines internal sarcomere shortening during fixed-end contraction

Gespeichert in:
Bibliographische Detailangaben
Deutscher übersetzter Titel:Die Interaktion zwischen der Serien-Compliance und der Sakomer-Kinetik bestimmt die interne Sarkomer-Verkuerzung bei endfixierter Kontraktion
Autor:Kawakami, Y.; Lieber, R.L.
Erschienen in:Journal of biomechanics
Veröffentlicht:33 (2000), 10, S. 1249-1255, Lit.
Format: Literatur (SPOLIT)
Publikationstyp: Zeitschriftenartikel
Medienart: Gedruckte Ressource Elektronische Ressource (online)
Sprache:Englisch
ISSN:0021-9290, 1873-2380
DOI:10.1016/S0021-9290(00)00095-6
Schlagworte:
Online Zugang:
Erfassungsnummer:PU199912408579
Quelle:BISp

Abstract des Autors

The interaction between contractile force and in-series compliance was investigated for the intact skeletal muscle-tendon unit (MTU) of Rana pipiens semitendinosus muscles during fixed-end contraction. It was hypothesized that internal sarcomere shortening is a function of the length-force characteristics of contractile and series elastic components. The MTUs (n=18) were dissected, and, while submerged in Ringer's solution, muscles were activated at nine muscle lengths ( -2 to +6 mm relative to optimal length in 1 mm intervals), while measuring muscle force and sarcomere length (SL) by laser diffraction. The MTU was clamped either at the bone (n=6), or at the proximal and distal ends of the aponeuroses (n=6). Muscle fibers were also trimmed along with aponeuroses down to 5-20 fibers and identical measurements were performed (n=6). The magnitude of shortening decreased as MTU length increased. The magnitude of shortening ranged from -0.08 to 0.3 micro-m, and there was no significant difference between deltaSL as a function of clamp location. When aponeuroses were trimmed, sarcomere shortening was not observed at L0 and longer. These results suggest that the aponeurosis is the major contributor to in-series compliance. Results also support our hypothesis but there also appear to be other factors affecting internal sarcomere shortening. The functional consequence of internal sarcomere shortening as a function of sarcomere length was to skew the muscle length-tension relationship to longer sarcomere lengths. Verf.-Referat