Regional differences in nitric oxide-mediated relaxation of the rabbit sphincter of Oddi

J. Lonovics, Jakab Ildikó, Judith Szilvássy, Z. Szilvássy

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

We studied the role of the l-arginine-nitric oxide (NO) pathway in non-adrenergic, non-cholinergic (NANC) relaxation of the rabbit sphincter of Oddi by recording changes in isometric tension in response to electrical field stimulation in two series of experiments. In a first set of experiments, biliary sphincters of Oddi removed from New Zealand white rabbits were placed horizontally in an organ bath containing oxygenized, buffered (pH 7.4) Krebs solution. Contractile responses of the whole sphincter to field stimulation were determined. In the second set of experiments, sphincter of Oddi was divided into two parts and the effects of field stimulation wewe studied separately on areas close to the duodenal papilla (area I) and areas close to the common bile duct (area II). In the whole sphincter of Oddi, field stimulation induced an initial twitch-like contraction followed by relaxation proportional to the number of stimuli (3 and 10 stimuli at 20 Hz, 50 V, 0.1 ms). The magnitude of the contractile responses was considerably reduced by 1 μM atropine, phentolamine and oxprenolol (NANC solution). Field stimulation produced dose-dependent contractions of both segments of sphincter of Oddi in response to the same protocol as used with whole sphincter of Oddi. However, preincubation with NANC solution produced monophasic relaxation in response to field stimulation in area I, whereas area II preparations such as the whole sphincter of Oddi respondend with contractions followed by minimal relaxations. Field stimulation failed to induce either contractions or relaxations in the presence of 1 μM tetrodotoxin. 30 μM NG-nitro-l-arginine methyl ester abolished NANC relaxation in area I, but did not influence significantly contractile responses of area II, or the whole sphincter of Oddi. l-Arginine but not d-arginine (both 3 mM) reversed the inhibitory effect of NG-nitro-l-arginine on NANC relaxation in area I. We conclude that (i) the l-arginine-NO pathways is involved in NANC relaxation of sphincter of Oddi segment close to the duodenal papilla and (ii) that there are regional differences in NO-mediated relaxation of the sphincter of Oddi in rabbits.

Original languageEnglish
Pages (from-to)117-122
Number of pages6
JournalEuropean Journal of Pharmacology
Volume255
Issue number1-3
DOIs
Publication statusPublished - Apr 1 1994

Fingerprint

Sphincter of Oddi
Nitric Oxide
Rabbits
Arginine
Oxprenolol
Phentolamine
Tetrodotoxin
Common Bile Duct
Baths
Atropine
Electric Stimulation

Keywords

  • Field stimulation
  • Neural relaxation
  • Nitric oxide (NO)
  • Sphincter of Oddi

ASJC Scopus subject areas

  • Cellular and Molecular Neuroscience
  • Pharmacology

Cite this

Regional differences in nitric oxide-mediated relaxation of the rabbit sphincter of Oddi. / Lonovics, J.; Ildikó, Jakab; Szilvássy, Judith; Szilvássy, Z.

In: European Journal of Pharmacology, Vol. 255, No. 1-3, 01.04.1994, p. 117-122.

Research output: Contribution to journalArticle

@article{47440f65886f41e085262d3d9a0454a5,
title = "Regional differences in nitric oxide-mediated relaxation of the rabbit sphincter of Oddi",
abstract = "We studied the role of the l-arginine-nitric oxide (NO) pathway in non-adrenergic, non-cholinergic (NANC) relaxation of the rabbit sphincter of Oddi by recording changes in isometric tension in response to electrical field stimulation in two series of experiments. In a first set of experiments, biliary sphincters of Oddi removed from New Zealand white rabbits were placed horizontally in an organ bath containing oxygenized, buffered (pH 7.4) Krebs solution. Contractile responses of the whole sphincter to field stimulation were determined. In the second set of experiments, sphincter of Oddi was divided into two parts and the effects of field stimulation wewe studied separately on areas close to the duodenal papilla (area I) and areas close to the common bile duct (area II). In the whole sphincter of Oddi, field stimulation induced an initial twitch-like contraction followed by relaxation proportional to the number of stimuli (3 and 10 stimuli at 20 Hz, 50 V, 0.1 ms). The magnitude of the contractile responses was considerably reduced by 1 μM atropine, phentolamine and oxprenolol (NANC solution). Field stimulation produced dose-dependent contractions of both segments of sphincter of Oddi in response to the same protocol as used with whole sphincter of Oddi. However, preincubation with NANC solution produced monophasic relaxation in response to field stimulation in area I, whereas area II preparations such as the whole sphincter of Oddi respondend with contractions followed by minimal relaxations. Field stimulation failed to induce either contractions or relaxations in the presence of 1 μM tetrodotoxin. 30 μM NG-nitro-l-arginine methyl ester abolished NANC relaxation in area I, but did not influence significantly contractile responses of area II, or the whole sphincter of Oddi. l-Arginine but not d-arginine (both 3 mM) reversed the inhibitory effect of NG-nitro-l-arginine on NANC relaxation in area I. We conclude that (i) the l-arginine-NO pathways is involved in NANC relaxation of sphincter of Oddi segment close to the duodenal papilla and (ii) that there are regional differences in NO-mediated relaxation of the sphincter of Oddi in rabbits.",
keywords = "Field stimulation, Neural relaxation, Nitric oxide (NO), Sphincter of Oddi",
author = "J. Lonovics and Jakab Ildik{\'o} and Judith Szilv{\'a}ssy and Z. Szilv{\'a}ssy",
year = "1994",
month = "4",
day = "1",
doi = "10.1016/0014-2999(94)90089-2",
language = "English",
volume = "255",
pages = "117--122",
journal = "European Journal of Pharmacology",
issn = "0014-2999",
publisher = "Elsevier",
number = "1-3",

}

TY - JOUR

T1 - Regional differences in nitric oxide-mediated relaxation of the rabbit sphincter of Oddi

AU - Lonovics, J.

AU - Ildikó, Jakab

AU - Szilvássy, Judith

AU - Szilvássy, Z.

PY - 1994/4/1

Y1 - 1994/4/1

N2 - We studied the role of the l-arginine-nitric oxide (NO) pathway in non-adrenergic, non-cholinergic (NANC) relaxation of the rabbit sphincter of Oddi by recording changes in isometric tension in response to electrical field stimulation in two series of experiments. In a first set of experiments, biliary sphincters of Oddi removed from New Zealand white rabbits were placed horizontally in an organ bath containing oxygenized, buffered (pH 7.4) Krebs solution. Contractile responses of the whole sphincter to field stimulation were determined. In the second set of experiments, sphincter of Oddi was divided into two parts and the effects of field stimulation wewe studied separately on areas close to the duodenal papilla (area I) and areas close to the common bile duct (area II). In the whole sphincter of Oddi, field stimulation induced an initial twitch-like contraction followed by relaxation proportional to the number of stimuli (3 and 10 stimuli at 20 Hz, 50 V, 0.1 ms). The magnitude of the contractile responses was considerably reduced by 1 μM atropine, phentolamine and oxprenolol (NANC solution). Field stimulation produced dose-dependent contractions of both segments of sphincter of Oddi in response to the same protocol as used with whole sphincter of Oddi. However, preincubation with NANC solution produced monophasic relaxation in response to field stimulation in area I, whereas area II preparations such as the whole sphincter of Oddi respondend with contractions followed by minimal relaxations. Field stimulation failed to induce either contractions or relaxations in the presence of 1 μM tetrodotoxin. 30 μM NG-nitro-l-arginine methyl ester abolished NANC relaxation in area I, but did not influence significantly contractile responses of area II, or the whole sphincter of Oddi. l-Arginine but not d-arginine (both 3 mM) reversed the inhibitory effect of NG-nitro-l-arginine on NANC relaxation in area I. We conclude that (i) the l-arginine-NO pathways is involved in NANC relaxation of sphincter of Oddi segment close to the duodenal papilla and (ii) that there are regional differences in NO-mediated relaxation of the sphincter of Oddi in rabbits.

AB - We studied the role of the l-arginine-nitric oxide (NO) pathway in non-adrenergic, non-cholinergic (NANC) relaxation of the rabbit sphincter of Oddi by recording changes in isometric tension in response to electrical field stimulation in two series of experiments. In a first set of experiments, biliary sphincters of Oddi removed from New Zealand white rabbits were placed horizontally in an organ bath containing oxygenized, buffered (pH 7.4) Krebs solution. Contractile responses of the whole sphincter to field stimulation were determined. In the second set of experiments, sphincter of Oddi was divided into two parts and the effects of field stimulation wewe studied separately on areas close to the duodenal papilla (area I) and areas close to the common bile duct (area II). In the whole sphincter of Oddi, field stimulation induced an initial twitch-like contraction followed by relaxation proportional to the number of stimuli (3 and 10 stimuli at 20 Hz, 50 V, 0.1 ms). The magnitude of the contractile responses was considerably reduced by 1 μM atropine, phentolamine and oxprenolol (NANC solution). Field stimulation produced dose-dependent contractions of both segments of sphincter of Oddi in response to the same protocol as used with whole sphincter of Oddi. However, preincubation with NANC solution produced monophasic relaxation in response to field stimulation in area I, whereas area II preparations such as the whole sphincter of Oddi respondend with contractions followed by minimal relaxations. Field stimulation failed to induce either contractions or relaxations in the presence of 1 μM tetrodotoxin. 30 μM NG-nitro-l-arginine methyl ester abolished NANC relaxation in area I, but did not influence significantly contractile responses of area II, or the whole sphincter of Oddi. l-Arginine but not d-arginine (both 3 mM) reversed the inhibitory effect of NG-nitro-l-arginine on NANC relaxation in area I. We conclude that (i) the l-arginine-NO pathways is involved in NANC relaxation of sphincter of Oddi segment close to the duodenal papilla and (ii) that there are regional differences in NO-mediated relaxation of the sphincter of Oddi in rabbits.

KW - Field stimulation

KW - Neural relaxation

KW - Nitric oxide (NO)

KW - Sphincter of Oddi

UR - http://www.scopus.com/inward/record.url?scp=0028210649&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0028210649&partnerID=8YFLogxK

U2 - 10.1016/0014-2999(94)90089-2

DO - 10.1016/0014-2999(94)90089-2

M3 - Article

VL - 255

SP - 117

EP - 122

JO - European Journal of Pharmacology

JF - European Journal of Pharmacology

SN - 0014-2999

IS - 1-3

ER -