TY - JOUR
T1 - Relationships between resting tension and mechanical properties of papillary muscle.
AU - Templeton, G.
AU - Adcock, R.
AU - Willerson, J. T.
AU - Nardizzi, L.
AU - Wildenthal, K.
AU - Mitchell, J. H.
PY - 1976/12
Y1 - 1976/12
N2 - The influence on mechanical properties of changes in resting tension over a range from 0.5 to 4.5 g was investigated in 12 isolated cat papillary muscles. At each resting tension, the muscles contracted isometrically with the exception of an externally applied sinusoidal stretch of 0.5% Lmax (deltaL) and 20 Hz. Stiffness (deltaT/deltaL) was determined from deltaL and the peak amplitudes (deltaT) of the individual cycles from the sinusoidal component of tension. Assuming that the muscle and experimental apparatus behaved as a linear second-order mechanical system, it was possible to divide stiffness into its elastic and viscous components. During rest, total stiffness and its components were linearly related to tension. During contraction, stiffness and its elastic component were linearly related to tension. Furthermore, increasing resting tension increased the intercept and decreased the slope of this linear stiffness-tension relationship. The relationship between viscous stiffness and tension during contraction is more complex in that it is a direct relationship at low resting tensions, but an inverse one at high resting tensions.
AB - The influence on mechanical properties of changes in resting tension over a range from 0.5 to 4.5 g was investigated in 12 isolated cat papillary muscles. At each resting tension, the muscles contracted isometrically with the exception of an externally applied sinusoidal stretch of 0.5% Lmax (deltaL) and 20 Hz. Stiffness (deltaT/deltaL) was determined from deltaL and the peak amplitudes (deltaT) of the individual cycles from the sinusoidal component of tension. Assuming that the muscle and experimental apparatus behaved as a linear second-order mechanical system, it was possible to divide stiffness into its elastic and viscous components. During rest, total stiffness and its components were linearly related to tension. During contraction, stiffness and its elastic component were linearly related to tension. Furthermore, increasing resting tension increased the intercept and decreased the slope of this linear stiffness-tension relationship. The relationship between viscous stiffness and tension during contraction is more complex in that it is a direct relationship at low resting tensions, but an inverse one at high resting tensions.
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U2 - 10.1152/ajplegacy.1976.231.6.1679
DO - 10.1152/ajplegacy.1976.231.6.1679
M3 - Article
C2 - 990106
AN - SCOPUS:0017083499
SN - 0002-9513
VL - 231
SP - 1679
EP - 1685
JO - The American journal of physiology
JF - The American journal of physiology
IS - 6
ER -