Evidence for muscarinic inhibitory neurotransmission in rodent small intestine

Thomas Nowak, B. Harrington, J. H. Kalbfleisch

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

The influence of cholinergic and noncholinergic inhibitory nerves was examined in circular and longitudinal muscle from the duodenum. Rodent proximal small intestine was cut into strips measuring 6.0 x 10.0 mm. Strips cut along the oral-caudal axis were called longitudinal strips, whereas those cut 90° to that axis were called circular strips. The strips were stretched to their optimal lengths and subjected to electrical field stimulation in the presence of various concentrations of atropine, pirenzepine or McN-A-343-11. All three drugs inhibited field-stimulated contraction responses and produced or augmented relaxation responses in both muscle layers. All relaxation responses were abolished by tetrodotoxin, indicating they were due to excitation of inhibitory nerves. For each response examined atropine was significantly more potent than pirenzepine (relative potency ratio, 13.36-95.74). The inhibitory effect of McN-A-343-11 on longitudinal muscle was antagonized by both atropine and pirenzepine, indicating the recruitment of cholinergic inhibitory nerves. Neither atropine nor pirenzepine had any effect on inhibitory responses produced by McN-A-343-11 in circular muscle, indicating the recruitment of noncholinergic inhibitory nerves. McN-A-343-11 also increased spontaneous contraction amplitudes in both muscle layers by a direct (tetrodotoxin-resistant) effect on smooth muscle. This effect was also antagonized by atropine and pirenzepine. Thus, both cholinergic and noncholinergic nerves participate in inhibitory neuromuscular transmission in the small intestine. Circular muscle is dominated by a noncholinergic inhibitory innervation. Longitudinal muscle appears to be controlled by both cholinergic and noncholinergic inhibitory nerves.

Original languageEnglish (US)
Pages (from-to)573-580
Number of pages8
JournalJournal of Pharmacology and Experimental Therapeutics
Volume248
Issue number2
StatePublished - 1989
Externally publishedYes

Fingerprint

Synaptic Transmission
Pirenzepine
Cholinergic Agents
Small Intestine
(4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethylammonium Chloride
Rodentia
Atropine
Muscles
Tetrodotoxin
Duodenum
Electric Stimulation
Smooth Muscle
Pharmaceutical Preparations

ASJC Scopus subject areas

  • Pharmacology

Cite this

Evidence for muscarinic inhibitory neurotransmission in rodent small intestine. / Nowak, Thomas; Harrington, B.; Kalbfleisch, J. H.

In: Journal of Pharmacology and Experimental Therapeutics, Vol. 248, No. 2, 1989, p. 573-580.

Research output: Contribution to journalArticle

@article{fb0a1398981a4fbb86b196cc473412b5,
title = "Evidence for muscarinic inhibitory neurotransmission in rodent small intestine",
abstract = "The influence of cholinergic and noncholinergic inhibitory nerves was examined in circular and longitudinal muscle from the duodenum. Rodent proximal small intestine was cut into strips measuring 6.0 x 10.0 mm. Strips cut along the oral-caudal axis were called longitudinal strips, whereas those cut 90° to that axis were called circular strips. The strips were stretched to their optimal lengths and subjected to electrical field stimulation in the presence of various concentrations of atropine, pirenzepine or McN-A-343-11. All three drugs inhibited field-stimulated contraction responses and produced or augmented relaxation responses in both muscle layers. All relaxation responses were abolished by tetrodotoxin, indicating they were due to excitation of inhibitory nerves. For each response examined atropine was significantly more potent than pirenzepine (relative potency ratio, 13.36-95.74). The inhibitory effect of McN-A-343-11 on longitudinal muscle was antagonized by both atropine and pirenzepine, indicating the recruitment of cholinergic inhibitory nerves. Neither atropine nor pirenzepine had any effect on inhibitory responses produced by McN-A-343-11 in circular muscle, indicating the recruitment of noncholinergic inhibitory nerves. McN-A-343-11 also increased spontaneous contraction amplitudes in both muscle layers by a direct (tetrodotoxin-resistant) effect on smooth muscle. This effect was also antagonized by atropine and pirenzepine. Thus, both cholinergic and noncholinergic nerves participate in inhibitory neuromuscular transmission in the small intestine. Circular muscle is dominated by a noncholinergic inhibitory innervation. Longitudinal muscle appears to be controlled by both cholinergic and noncholinergic inhibitory nerves.",
author = "Thomas Nowak and B. Harrington and Kalbfleisch, {J. H.}",
year = "1989",
language = "English (US)",
volume = "248",
pages = "573--580",
journal = "Journal of Pharmacology and Experimental Therapeutics",
issn = "0022-3565",
publisher = "American Society for Pharmacology and Experimental Therapeutics",
number = "2",

}

TY - JOUR

T1 - Evidence for muscarinic inhibitory neurotransmission in rodent small intestine

AU - Nowak, Thomas

AU - Harrington, B.

AU - Kalbfleisch, J. H.

PY - 1989

Y1 - 1989

N2 - The influence of cholinergic and noncholinergic inhibitory nerves was examined in circular and longitudinal muscle from the duodenum. Rodent proximal small intestine was cut into strips measuring 6.0 x 10.0 mm. Strips cut along the oral-caudal axis were called longitudinal strips, whereas those cut 90° to that axis were called circular strips. The strips were stretched to their optimal lengths and subjected to electrical field stimulation in the presence of various concentrations of atropine, pirenzepine or McN-A-343-11. All three drugs inhibited field-stimulated contraction responses and produced or augmented relaxation responses in both muscle layers. All relaxation responses were abolished by tetrodotoxin, indicating they were due to excitation of inhibitory nerves. For each response examined atropine was significantly more potent than pirenzepine (relative potency ratio, 13.36-95.74). The inhibitory effect of McN-A-343-11 on longitudinal muscle was antagonized by both atropine and pirenzepine, indicating the recruitment of cholinergic inhibitory nerves. Neither atropine nor pirenzepine had any effect on inhibitory responses produced by McN-A-343-11 in circular muscle, indicating the recruitment of noncholinergic inhibitory nerves. McN-A-343-11 also increased spontaneous contraction amplitudes in both muscle layers by a direct (tetrodotoxin-resistant) effect on smooth muscle. This effect was also antagonized by atropine and pirenzepine. Thus, both cholinergic and noncholinergic nerves participate in inhibitory neuromuscular transmission in the small intestine. Circular muscle is dominated by a noncholinergic inhibitory innervation. Longitudinal muscle appears to be controlled by both cholinergic and noncholinergic inhibitory nerves.

AB - The influence of cholinergic and noncholinergic inhibitory nerves was examined in circular and longitudinal muscle from the duodenum. Rodent proximal small intestine was cut into strips measuring 6.0 x 10.0 mm. Strips cut along the oral-caudal axis were called longitudinal strips, whereas those cut 90° to that axis were called circular strips. The strips were stretched to their optimal lengths and subjected to electrical field stimulation in the presence of various concentrations of atropine, pirenzepine or McN-A-343-11. All three drugs inhibited field-stimulated contraction responses and produced or augmented relaxation responses in both muscle layers. All relaxation responses were abolished by tetrodotoxin, indicating they were due to excitation of inhibitory nerves. For each response examined atropine was significantly more potent than pirenzepine (relative potency ratio, 13.36-95.74). The inhibitory effect of McN-A-343-11 on longitudinal muscle was antagonized by both atropine and pirenzepine, indicating the recruitment of cholinergic inhibitory nerves. Neither atropine nor pirenzepine had any effect on inhibitory responses produced by McN-A-343-11 in circular muscle, indicating the recruitment of noncholinergic inhibitory nerves. McN-A-343-11 also increased spontaneous contraction amplitudes in both muscle layers by a direct (tetrodotoxin-resistant) effect on smooth muscle. This effect was also antagonized by atropine and pirenzepine. Thus, both cholinergic and noncholinergic nerves participate in inhibitory neuromuscular transmission in the small intestine. Circular muscle is dominated by a noncholinergic inhibitory innervation. Longitudinal muscle appears to be controlled by both cholinergic and noncholinergic inhibitory nerves.

UR - http://www.scopus.com/inward/record.url?scp=0024591216&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0024591216&partnerID=8YFLogxK

M3 - Article

VL - 248

SP - 573

EP - 580

JO - Journal of Pharmacology and Experimental Therapeutics

JF - Journal of Pharmacology and Experimental Therapeutics

SN - 0022-3565

IS - 2

ER -