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Influence of ATP, ADP and AMPPNP on the energetics of contraction in skinned smooth muscle

Arner, Anders LU ; Hellstrand, Per LU and Ruegg, J C (1987) In Progress in Clinical and Biological Research 245. p.43-57
Abstract
The contraction of smooth muscle is influenced by the substrate MgATP and the product MgADP. The effects on force, shortening velocity and ATP-turnover, are consistent with an influence on the kinetics of cross-bridge cycling. Part of these effects are mediated via an influence on the regulation of contraction by myosin light chain phosphorylation. Results from preparations activated by thiophosphorylation, show that MgATP and MgADP also interact directly at the cross-bridge level, and are consistent with MgADP acting as a competitive ATP-analogue. The slow shortening velocity and decreased rate of ATP-induced relaxation from rigor in the presence of MgADP, suggest an inhibition of cross-bridge detachment. The rate of ATP-turnover was... (More)
The contraction of smooth muscle is influenced by the substrate MgATP and the product MgADP. The effects on force, shortening velocity and ATP-turnover, are consistent with an influence on the kinetics of cross-bridge cycling. Part of these effects are mediated via an influence on the regulation of contraction by myosin light chain phosphorylation. Results from preparations activated by thiophosphorylation, show that MgATP and MgADP also interact directly at the cross-bridge level, and are consistent with MgADP acting as a competitive ATP-analogue. The slow shortening velocity and decreased rate of ATP-induced relaxation from rigor in the presence of MgADP, suggest an inhibition of cross-bridge detachment. The rate of ATP-turnover was decreased in the presence of the nonhydrolyzable ATP-analogue AMPPNP. These results may contribute to the characterization of the biochemical reactions in the structurally organized smooth muscle contractile system. In addition, the influence of MgATP and MgADP on smooth muscle contraction suggest that the concentrations of substrate and products, at the level of the contractile proteins, may constitute important regulatory factors in vivo under conditions, such as hypoxia and ischemia, associated with impaired cellular energy supply. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Progress in Clinical and Biological Research
volume
245
pages
43 - 57
publisher
John Wiley & Sons
external identifiers
  • pmid:3685021
  • scopus:0023461923
ISSN
0361-7742
language
English
LU publication?
yes
id
a2505d93-4027-4e63-abe4-90fa39008ce1 (old id 1103920)
date added to LUP
2008-08-08 16:28:54
date last changed
2017-08-06 04:43:16
@article{a2505d93-4027-4e63-abe4-90fa39008ce1,
  abstract     = {The contraction of smooth muscle is influenced by the substrate MgATP and the product MgADP. The effects on force, shortening velocity and ATP-turnover, are consistent with an influence on the kinetics of cross-bridge cycling. Part of these effects are mediated via an influence on the regulation of contraction by myosin light chain phosphorylation. Results from preparations activated by thiophosphorylation, show that MgATP and MgADP also interact directly at the cross-bridge level, and are consistent with MgADP acting as a competitive ATP-analogue. The slow shortening velocity and decreased rate of ATP-induced relaxation from rigor in the presence of MgADP, suggest an inhibition of cross-bridge detachment. The rate of ATP-turnover was decreased in the presence of the nonhydrolyzable ATP-analogue AMPPNP. These results may contribute to the characterization of the biochemical reactions in the structurally organized smooth muscle contractile system. In addition, the influence of MgATP and MgADP on smooth muscle contraction suggest that the concentrations of substrate and products, at the level of the contractile proteins, may constitute important regulatory factors in vivo under conditions, such as hypoxia and ischemia, associated with impaired cellular energy supply.},
  author       = {Arner, Anders and Hellstrand, Per and Ruegg, J C},
  issn         = {0361-7742},
  language     = {eng},
  pages        = {43--57},
  publisher    = {John Wiley & Sons},
  series       = {Progress in Clinical and Biological Research},
  title        = {Influence of ATP, ADP and AMPPNP on the energetics of contraction in skinned smooth muscle},
  volume       = {245},
  year         = {1987},
}