The frequency response of smooth muscle stiffness during Ca2+- activated contraction

Guay Haur Shue, Frank V. Brozovich

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

To investigate the mechanism of smooth muscle contraction, the frequency response of the muscle stiffness of single β-escin permeabilized smooth muscle cells in the relaxed state was studied. Also, the response was continuously monitored for 3 min from the beginning of the exchange of relaxing solution to activating solution, and then at 5-min intervals for up to 20 min. The frequency response (30 Hz bandwidth, 0.33 Hz (or 0.2 Hz) resolution) was calculated from the Fourier-transformed force and length sampled during a 3-s (or 5-s) constant-amplitude length perturbation of increasing-frequency (1-32 Hz) sine waves. In the re axed state, a large negative phase angle was observed, which suggests the existence of attached energy generating cross-bridges. As the activation progressed, the muscle stiffness and phase angle steadily increased; these increases gradually extended to higher frequencies, and reached a steady state by 100 s after activation or ~40 s after stiffness began to increase. The results suggest that a fixed distribution of cross-bridge states was reached after 40 s of Ca2+ activation and the cross-bridge cycling rate did not change during the period of force maintenance.

Original languageEnglish (US)
Pages (from-to)2361-2369
Number of pages9
JournalBiophysical Journal
Volume76
Issue number5
StatePublished - 1999
Externally publishedYes

Fingerprint

Smooth Muscle
Escin
Muscles
Muscle Contraction
Smooth Muscle Myocytes
Maintenance

ASJC Scopus subject areas

  • Biophysics

Cite this

The frequency response of smooth muscle stiffness during Ca2+- activated contraction. / Shue, Guay Haur; Brozovich, Frank V.

In: Biophysical Journal, Vol. 76, No. 5, 1999, p. 2361-2369.

Research output: Contribution to journalArticle

Shue, Guay Haur ; Brozovich, Frank V. / The frequency response of smooth muscle stiffness during Ca2+- activated contraction. In: Biophysical Journal. 1999 ; Vol. 76, No. 5. pp. 2361-2369.
@article{dbb00de7ea794beeba570298ab96bed1,
title = "The frequency response of smooth muscle stiffness during Ca2+- activated contraction",
abstract = "To investigate the mechanism of smooth muscle contraction, the frequency response of the muscle stiffness of single β-escin permeabilized smooth muscle cells in the relaxed state was studied. Also, the response was continuously monitored for 3 min from the beginning of the exchange of relaxing solution to activating solution, and then at 5-min intervals for up to 20 min. The frequency response (30 Hz bandwidth, 0.33 Hz (or 0.2 Hz) resolution) was calculated from the Fourier-transformed force and length sampled during a 3-s (or 5-s) constant-amplitude length perturbation of increasing-frequency (1-32 Hz) sine waves. In the re axed state, a large negative phase angle was observed, which suggests the existence of attached energy generating cross-bridges. As the activation progressed, the muscle stiffness and phase angle steadily increased; these increases gradually extended to higher frequencies, and reached a steady state by 100 s after activation or ~40 s after stiffness began to increase. The results suggest that a fixed distribution of cross-bridge states was reached after 40 s of Ca2+ activation and the cross-bridge cycling rate did not change during the period of force maintenance.",
author = "Shue, {Guay Haur} and Brozovich, {Frank V.}",
year = "1999",
language = "English (US)",
volume = "76",
pages = "2361--2369",
journal = "Biophysical Journal",
issn = "0006-3495",
publisher = "Biophysical Society",
number = "5",

}

TY - JOUR

T1 - The frequency response of smooth muscle stiffness during Ca2+- activated contraction

AU - Shue, Guay Haur

AU - Brozovich, Frank V.

PY - 1999

Y1 - 1999

N2 - To investigate the mechanism of smooth muscle contraction, the frequency response of the muscle stiffness of single β-escin permeabilized smooth muscle cells in the relaxed state was studied. Also, the response was continuously monitored for 3 min from the beginning of the exchange of relaxing solution to activating solution, and then at 5-min intervals for up to 20 min. The frequency response (30 Hz bandwidth, 0.33 Hz (or 0.2 Hz) resolution) was calculated from the Fourier-transformed force and length sampled during a 3-s (or 5-s) constant-amplitude length perturbation of increasing-frequency (1-32 Hz) sine waves. In the re axed state, a large negative phase angle was observed, which suggests the existence of attached energy generating cross-bridges. As the activation progressed, the muscle stiffness and phase angle steadily increased; these increases gradually extended to higher frequencies, and reached a steady state by 100 s after activation or ~40 s after stiffness began to increase. The results suggest that a fixed distribution of cross-bridge states was reached after 40 s of Ca2+ activation and the cross-bridge cycling rate did not change during the period of force maintenance.

AB - To investigate the mechanism of smooth muscle contraction, the frequency response of the muscle stiffness of single β-escin permeabilized smooth muscle cells in the relaxed state was studied. Also, the response was continuously monitored for 3 min from the beginning of the exchange of relaxing solution to activating solution, and then at 5-min intervals for up to 20 min. The frequency response (30 Hz bandwidth, 0.33 Hz (or 0.2 Hz) resolution) was calculated from the Fourier-transformed force and length sampled during a 3-s (or 5-s) constant-amplitude length perturbation of increasing-frequency (1-32 Hz) sine waves. In the re axed state, a large negative phase angle was observed, which suggests the existence of attached energy generating cross-bridges. As the activation progressed, the muscle stiffness and phase angle steadily increased; these increases gradually extended to higher frequencies, and reached a steady state by 100 s after activation or ~40 s after stiffness began to increase. The results suggest that a fixed distribution of cross-bridge states was reached after 40 s of Ca2+ activation and the cross-bridge cycling rate did not change during the period of force maintenance.

UR - http://www.scopus.com/inward/record.url?scp=0033064925&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0033064925&partnerID=8YFLogxK

M3 - Article

C2 - 10233055

AN - SCOPUS:0033064925

VL - 76

SP - 2361

EP - 2369

JO - Biophysical Journal

JF - Biophysical Journal

SN - 0006-3495

IS - 5

ER -