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Effects of polyamines on intracellular calcium and mechanical activity in smooth muscle of guinea-pig taenia coli

Nilsson, Bengt-Olof LU and Hellstrand, Per LU (1993) In Acta Physiologica Scandinavica 148(1). p.37-43
Abstract
The effects of the polyamines putrescine, spermidine and spermine on the mechanical activity in smooth muscle from guinea-pig taenia coli were investigated. Tissue concentrations of spermidine and spermine were about 240 and 160 nmol g-1, respectively, while the putrescine concentration was much lower (4 nmol g-1). Intracellular [Ca2+] was determined using the Fura-2 method and the effects of extracellularly applied polyamines were observed. Spermine (10(-5)-10(-3) mol l-1) dose-dependently inhibited spontaneous contractions as well as contractions induced by 20-25 mmol l-1 KCl, with 10(-3) mol l-1 spermine giving nearly total relaxation. Spermidine (10(-3) mol l-1) relaxed a 20 mmol l-1 KCl contracture, while putrescine had no effect. A... (More)
The effects of the polyamines putrescine, spermidine and spermine on the mechanical activity in smooth muscle from guinea-pig taenia coli were investigated. Tissue concentrations of spermidine and spermine were about 240 and 160 nmol g-1, respectively, while the putrescine concentration was much lower (4 nmol g-1). Intracellular [Ca2+] was determined using the Fura-2 method and the effects of extracellularly applied polyamines were observed. Spermine (10(-5)-10(-3) mol l-1) dose-dependently inhibited spontaneous contractions as well as contractions induced by 20-25 mmol l-1 KCl, with 10(-3) mol l-1 spermine giving nearly total relaxation. Spermidine (10(-3) mol l-1) relaxed a 20 mmol l-1 KCl contracture, while putrescine had no effect. A decrease in intracellular [Ca2+] accompanied the relaxation induced by spermine. In contrast to the effects on spontaneous activity and intermediate [KCl], both the contraction and the accompanying increase in intracellular [Ca2+] induced by 90-120 mmol l-1 KCl were unaffected by spermine. Spermine did not affect the maximal Ca(2+)-induced force of chemically skinned taenia coli preparations, but a small potentiating effect on the Ca2+ sensitivity was observed. The results indicate that the relaxation induced by spermine depends on an intact cell membrane. Furthermore, the relaxing effect is due to decreased intracellular [Ca2+] and seems to occur only when the contraction is elicited by repetitive action potentials, and not by sustained depolarization. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Acta Physiologica Scandinavica
volume
148
issue
1
pages
37 - 43
publisher
Wiley-Blackwell
external identifiers
  • pmid:8333295
  • scopus:0027153908
ISSN
0001-6772
DOI
10.1111/j.1748-1716.1993.tb09529.x
language
English
LU publication?
yes
id
bc706551-60de-4f34-bfc8-b8aaf6a3cd11 (old id 1107371)
date added to LUP
2008-07-30 16:59:51
date last changed
2017-01-01 06:57:01
@article{bc706551-60de-4f34-bfc8-b8aaf6a3cd11,
  abstract     = {The effects of the polyamines putrescine, spermidine and spermine on the mechanical activity in smooth muscle from guinea-pig taenia coli were investigated. Tissue concentrations of spermidine and spermine were about 240 and 160 nmol g-1, respectively, while the putrescine concentration was much lower (4 nmol g-1). Intracellular [Ca2+] was determined using the Fura-2 method and the effects of extracellularly applied polyamines were observed. Spermine (10(-5)-10(-3) mol l-1) dose-dependently inhibited spontaneous contractions as well as contractions induced by 20-25 mmol l-1 KCl, with 10(-3) mol l-1 spermine giving nearly total relaxation. Spermidine (10(-3) mol l-1) relaxed a 20 mmol l-1 KCl contracture, while putrescine had no effect. A decrease in intracellular [Ca2+] accompanied the relaxation induced by spermine. In contrast to the effects on spontaneous activity and intermediate [KCl], both the contraction and the accompanying increase in intracellular [Ca2+] induced by 90-120 mmol l-1 KCl were unaffected by spermine. Spermine did not affect the maximal Ca(2+)-induced force of chemically skinned taenia coli preparations, but a small potentiating effect on the Ca2+ sensitivity was observed. The results indicate that the relaxation induced by spermine depends on an intact cell membrane. Furthermore, the relaxing effect is due to decreased intracellular [Ca2+] and seems to occur only when the contraction is elicited by repetitive action potentials, and not by sustained depolarization.},
  author       = {Nilsson, Bengt-Olof and Hellstrand, Per},
  issn         = {0001-6772},
  language     = {eng},
  number       = {1},
  pages        = {37--43},
  publisher    = {Wiley-Blackwell},
  series       = {Acta Physiologica Scandinavica},
  title        = {Effects of polyamines on intracellular calcium and mechanical activity in smooth muscle of guinea-pig taenia coli},
  url          = {http://dx.doi.org/10.1111/j.1748-1716.1993.tb09529.x},
  volume       = {148},
  year         = {1993},
}