Cross-bridge kinetics and shortening in smooth muscle
(1994) In Canadian Journal of Physiology and Pharmacology 72(11). p.1334-1337- Abstract
- Stiffness measurements were performed on smooth muscle preparations from guinea-pig taenia coli to obtain information on the number of attached cross bridges under varying contractile conditions. The normalized stiffness of the cross-bridge system in smooth muscle may be of a magnitude similar to that assumed in skeletal muscle. Transition from isometric contraction to unloaded shortening was associated with a decrease in stiffness to 50% or less of the isometric value, slightly higher than that found in skeletal muscle fibers. Comparison of phasic (5 s) and tonic (5 min) contractions showed lower Vmax, intracellular [Ca2+], and myosin 20 kDa light chain phosphorylation at 5 min, indicating development of a latch state. Isometric force and... (More)
- Stiffness measurements were performed on smooth muscle preparations from guinea-pig taenia coli to obtain information on the number of attached cross bridges under varying contractile conditions. The normalized stiffness of the cross-bridge system in smooth muscle may be of a magnitude similar to that assumed in skeletal muscle. Transition from isometric contraction to unloaded shortening was associated with a decrease in stiffness to 50% or less of the isometric value, slightly higher than that found in skeletal muscle fibers. Comparison of phasic (5 s) and tonic (5 min) contractions showed lower Vmax, intracellular [Ca2+], and myosin 20 kDa light chain phosphorylation at 5 min, indicating development of a latch state. Isometric force and stiffness were identical in the two types of contraction. However, stiffness during unloaded shortening was greater in the latch state, which may be the result of the presence of a population of cross bridges with a low rate constant for detachment. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1108286
- author
- Hellstrand, Per LU
- organization
- publishing date
- 1994
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Canadian Journal of Physiology and Pharmacology
- volume
- 72
- issue
- 11
- pages
- 1334 - 1337
- publisher
- National Research Council Canada
- external identifiers
-
- pmid:7767875
- scopus:0028633626
- ISSN
- 0008-4212
- language
- English
- LU publication?
- yes
- id
- efc4e3ac-f155-4dd0-921d-556b0611077c (old id 1108286)
- date added to LUP
- 2016-04-01 12:15:46
- date last changed
- 2021-01-03 07:34:32
@article{efc4e3ac-f155-4dd0-921d-556b0611077c,
abstract = {{Stiffness measurements were performed on smooth muscle preparations from guinea-pig taenia coli to obtain information on the number of attached cross bridges under varying contractile conditions. The normalized stiffness of the cross-bridge system in smooth muscle may be of a magnitude similar to that assumed in skeletal muscle. Transition from isometric contraction to unloaded shortening was associated with a decrease in stiffness to 50% or less of the isometric value, slightly higher than that found in skeletal muscle fibers. Comparison of phasic (5 s) and tonic (5 min) contractions showed lower Vmax, intracellular [Ca2+], and myosin 20 kDa light chain phosphorylation at 5 min, indicating development of a latch state. Isometric force and stiffness were identical in the two types of contraction. However, stiffness during unloaded shortening was greater in the latch state, which may be the result of the presence of a population of cross bridges with a low rate constant for detachment.}},
author = {{Hellstrand, Per}},
issn = {{0008-4212}},
language = {{eng}},
number = {{11}},
pages = {{1334--1337}},
publisher = {{National Research Council Canada}},
series = {{Canadian Journal of Physiology and Pharmacology}},
title = {{Cross-bridge kinetics and shortening in smooth muscle}},
volume = {{72}},
year = {{1994}},
}