Action of myenteric GABAergic neurons in the guinea pig stomach

Li Hsueh Tsai, Wuhong Tsai, Jang Yen Wu

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

GABAergic neurons in the guinea pig stomach were localized immunocytochemically using antibodies against its synthesizing enzyme, l-glutamate decarboxylase (GAD). Numerous ganglion cells and nerve bundles in the myenteric plexus were found to be GAD-positive, while the longitudinal muscle, submucosa and mucosa were largely devoid of GABAergic innervation. The distribution of GABAergic neurons and their processes in both myenteric ganglia and circular muscle is rather uneven throughout the stomach. GABA elicited contraction of the longitudinal fashion (LF) strips of the body and antrum of guinea pig stomach in a concentration-dependent fashion with a maximal response at 10-7 M and 10-5 M, respectively. GABA-induced contraction appears to be mediated by the GABAA receptor and not the GABAB receptor, since the action is blocked by bicuculline, a GABAA receptor antagonist. Furthermore, GABAA agonists e.g. muscimol produced even stronger responses than GABA itself while GABAB agonist, (-)baclofen had no effect in eliciting muscle contraction. The GABAA receptor is desensitized by prolonged exposure to its agonists such as GABA and muscimol. However, no such desensitization was observed for the muscarinic cholinergic receptor. The GABA action in eliciting smooth muscle contraction seems to involve two components, one is scopolamine and tetrodotoxin (TTX) sensitive, and the other one is insensitive to scopolamine and TTX. It is proposed that the scopolamine- and TTX-sensitive component acts through a direct or indirect interaction between GABAergic and cholinergic neurons whereas the scopolamine- and TTX-insensitive component acts directly upon the smooth muscle.

Original languageEnglish
Pages (from-to)187-193
Number of pages7
JournalNeurochemistry International
Volume23
Issue number2
DOIs
Publication statusPublished - 1993

Fingerprint

GABAergic Neurons
Scopolamine Hydrobromide
gamma-Aminobutyric Acid
Tetrodotoxin
Stomach
Guinea Pigs
Muscimol
Glutamate Decarboxylase
GABA-A Receptors
Muscle Contraction
Ganglia
Smooth Muscle
GABA-A Receptor Agonists
GABA-A Receptor Antagonists
Myenteric Plexus
Muscles
Baclofen
Cholinergic Neurons
Bicuculline
Cholinergic Receptors

ASJC Scopus subject areas

  • Cell Biology
  • Molecular Biology
  • Cellular and Molecular Neuroscience

Cite this

Action of myenteric GABAergic neurons in the guinea pig stomach. / Tsai, Li Hsueh; Tsai, Wuhong; Wu, Jang Yen.

In: Neurochemistry International, Vol. 23, No. 2, 1993, p. 187-193.

Research output: Contribution to journalArticle

Tsai, Li Hsueh ; Tsai, Wuhong ; Wu, Jang Yen. / Action of myenteric GABAergic neurons in the guinea pig stomach. In: Neurochemistry International. 1993 ; Vol. 23, No. 2. pp. 187-193.
@article{ea29b32eccef48c99e9402105939245c,
title = "Action of myenteric GABAergic neurons in the guinea pig stomach",
abstract = "GABAergic neurons in the guinea pig stomach were localized immunocytochemically using antibodies against its synthesizing enzyme, l-glutamate decarboxylase (GAD). Numerous ganglion cells and nerve bundles in the myenteric plexus were found to be GAD-positive, while the longitudinal muscle, submucosa and mucosa were largely devoid of GABAergic innervation. The distribution of GABAergic neurons and their processes in both myenteric ganglia and circular muscle is rather uneven throughout the stomach. GABA elicited contraction of the longitudinal fashion (LF) strips of the body and antrum of guinea pig stomach in a concentration-dependent fashion with a maximal response at 10-7 M and 10-5 M, respectively. GABA-induced contraction appears to be mediated by the GABAA receptor and not the GABAB receptor, since the action is blocked by bicuculline, a GABAA receptor antagonist. Furthermore, GABAA agonists e.g. muscimol produced even stronger responses than GABA itself while GABAB agonist, (-)baclofen had no effect in eliciting muscle contraction. The GABAA receptor is desensitized by prolonged exposure to its agonists such as GABA and muscimol. However, no such desensitization was observed for the muscarinic cholinergic receptor. The GABA action in eliciting smooth muscle contraction seems to involve two components, one is scopolamine and tetrodotoxin (TTX) sensitive, and the other one is insensitive to scopolamine and TTX. It is proposed that the scopolamine- and TTX-sensitive component acts through a direct or indirect interaction between GABAergic and cholinergic neurons whereas the scopolamine- and TTX-insensitive component acts directly upon the smooth muscle.",
author = "Tsai, {Li Hsueh} and Wuhong Tsai and Wu, {Jang Yen}",
year = "1993",
doi = "10.1016/0197-0186(93)90096-N",
language = "English",
volume = "23",
pages = "187--193",
journal = "Neurochemistry International",
issn = "0197-0186",
publisher = "Elsevier Limited",
number = "2",

}

TY - JOUR

T1 - Action of myenteric GABAergic neurons in the guinea pig stomach

AU - Tsai, Li Hsueh

AU - Tsai, Wuhong

AU - Wu, Jang Yen

PY - 1993

Y1 - 1993

N2 - GABAergic neurons in the guinea pig stomach were localized immunocytochemically using antibodies against its synthesizing enzyme, l-glutamate decarboxylase (GAD). Numerous ganglion cells and nerve bundles in the myenteric plexus were found to be GAD-positive, while the longitudinal muscle, submucosa and mucosa were largely devoid of GABAergic innervation. The distribution of GABAergic neurons and their processes in both myenteric ganglia and circular muscle is rather uneven throughout the stomach. GABA elicited contraction of the longitudinal fashion (LF) strips of the body and antrum of guinea pig stomach in a concentration-dependent fashion with a maximal response at 10-7 M and 10-5 M, respectively. GABA-induced contraction appears to be mediated by the GABAA receptor and not the GABAB receptor, since the action is blocked by bicuculline, a GABAA receptor antagonist. Furthermore, GABAA agonists e.g. muscimol produced even stronger responses than GABA itself while GABAB agonist, (-)baclofen had no effect in eliciting muscle contraction. The GABAA receptor is desensitized by prolonged exposure to its agonists such as GABA and muscimol. However, no such desensitization was observed for the muscarinic cholinergic receptor. The GABA action in eliciting smooth muscle contraction seems to involve two components, one is scopolamine and tetrodotoxin (TTX) sensitive, and the other one is insensitive to scopolamine and TTX. It is proposed that the scopolamine- and TTX-sensitive component acts through a direct or indirect interaction between GABAergic and cholinergic neurons whereas the scopolamine- and TTX-insensitive component acts directly upon the smooth muscle.

AB - GABAergic neurons in the guinea pig stomach were localized immunocytochemically using antibodies against its synthesizing enzyme, l-glutamate decarboxylase (GAD). Numerous ganglion cells and nerve bundles in the myenteric plexus were found to be GAD-positive, while the longitudinal muscle, submucosa and mucosa were largely devoid of GABAergic innervation. The distribution of GABAergic neurons and their processes in both myenteric ganglia and circular muscle is rather uneven throughout the stomach. GABA elicited contraction of the longitudinal fashion (LF) strips of the body and antrum of guinea pig stomach in a concentration-dependent fashion with a maximal response at 10-7 M and 10-5 M, respectively. GABA-induced contraction appears to be mediated by the GABAA receptor and not the GABAB receptor, since the action is blocked by bicuculline, a GABAA receptor antagonist. Furthermore, GABAA agonists e.g. muscimol produced even stronger responses than GABA itself while GABAB agonist, (-)baclofen had no effect in eliciting muscle contraction. The GABAA receptor is desensitized by prolonged exposure to its agonists such as GABA and muscimol. However, no such desensitization was observed for the muscarinic cholinergic receptor. The GABA action in eliciting smooth muscle contraction seems to involve two components, one is scopolamine and tetrodotoxin (TTX) sensitive, and the other one is insensitive to scopolamine and TTX. It is proposed that the scopolamine- and TTX-sensitive component acts through a direct or indirect interaction between GABAergic and cholinergic neurons whereas the scopolamine- and TTX-insensitive component acts directly upon the smooth muscle.

UR - http://www.scopus.com/inward/record.url?scp=0027164565&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0027164565&partnerID=8YFLogxK

U2 - 10.1016/0197-0186(93)90096-N

DO - 10.1016/0197-0186(93)90096-N

M3 - Article

C2 - 8369742

AN - SCOPUS:0027164565

VL - 23

SP - 187

EP - 193

JO - Neurochemistry International

JF - Neurochemistry International

SN - 0197-0186

IS - 2

ER -