Search results for "Phaclofen"
showing 4 items of 4 documents
Functional evidence for GABA as modulator of the contractility of the longitudinal muscle in mouse duodenum: Role of GABAA and GABAC receptors
2007
We investigated, in vitro, the effects of gamma-aminobutyric acid (GABA) on the spontaneous mechanical activity of the longitudinal smooth muscle in mouse duodenum. GABA induced an excitatory effect, consisting in an increase in the basal tone, which was antagonized by the GABA(A)-receptor antagonist, bicuculline, potentiated by (1,2,5,6-Tetrahydropyridin-4-yl)methylphosphinic acid hydrate (TPMPA), a GABA(C)-receptor antagonist and it was not affected by phaclofen, a GABA(B)-receptor antagonist. Muscimol, GABA(A) receptor agonist, induced a contractile effect markedly reduced by bicuculline, tetrodotoxin (TTX), hexamethonium and atropine. Cis-4-aminocrotonic acid (CACA), a specific GABA(C) …
Age-related differences of γ-aminobutyric acid (GABA)ergic transmission in human colonic smooth muscle.
2021
Background: Enteric neurons undergo to functional changes during aging. We investigated the possible age-associated differences in enteric γ-aminobutyric acid (GABA)ergic transmission evaluating function and distribution of GABAergic receptors in human colon. Methods: Mechanical responses to GABA and GABA receptor agonists on slow phasic contractions were examined in vitro as changes in isometric tension in colonic muscle strips from young (<65 years old) and aged patients (>65 years old). GABAergic receptor expression was assessed by quantitative RT-PCR. Key Results: In both preparations GABA induced an excitatory effect, consisting in an increase in the basal tone, antagonized by th…
Opposite role played by GABAA and GABAB receptors in the modulation of peristaltic activity in mouse distal colon.
2014
We investigated the role of GABA on intestinal motility using as model the murine distal colon. Effects induced by GABA receptors recruitment were examined in whole colonic segments and isolated circular muscle preparations to analyze their influence on peristaltic reflex and on spontaneous and neurally-evoked contractions. Using a modified Trendelenburg set-up, rhythmic peristaltic contractions were evoked by gradual distension of the colonic segments. Spontaneous and neurally-evoked mechanical activity of circular muscle strips were recorded in vitro as changes in isometric tension. GABA, at low concentrations (10-50 µM), potentiated peristaltic activity and the neural cholinergic contrac…
Functional evidence for different roles of GABAA and GABAB receptors in modulating mouse gastric tone
2010
Abstract The aims of the present study were to investigate, using mouse whole stomach in vitro , the effects of γ-aminobutyric acid (GABA) and GABA receptor agonists on the spontaneous gastric tone, to examine the subtypes of GABA receptors involved in the responses and to determine the possible site(s) of action. GABA induced gastric relaxation, which was antagonized by the GABA A -receptor antagonist, bicuculline, potentiated by phaclofen, GABA B -receptor antagonist, but not affected by 1,2,5,6-Tetrahydropyridin-4-yl methylphosphinic acid hydrate (TPMPA), GABA C -receptor antagonist. Muscimol, GABA A -receptor agonist, mimicked GABA effects inducing relaxation, which was significantly re…