Using a brainstem slice preparation, we aimed to study the pre- and postsynaptic effects of glucagon-like peptide-1 (GLP-1) on synaptic transmission to identified pancreas-projecting vagal motoneurons. Following blockade of GABAergic mediated currents with bicuculline, perfusion with 100 nM GLP-1 increased both amplitude and frequency of excitatory postsynaptic currents (EPSCs) in 21 of 52 neurons. Perfusion with the GLP-1 selective agonist exendin-4 (100 nM), also increased the frequency of spontaneous EPSCs, while pretreatment with the GLP-1 selective antagonist, exendin 9-39, prevented the effects of GLP-1. In the presence of kynurenic acid to block ionotropic glutamatergic currents, perfusion with GLP-1 increased the frequency of inhibitory postsynaptic currents (IPSCs) in 28 of 74 neurons; in 14 of these responsive neurons, GLP-1 also increased IPSC amplitude, indicating actions at both pre- and postsynaptic sites. Perfusion with exendin-4 increased the frequency of spontaneous IPSCs, while pretreatment with exendin 9-39 prevented the effects of GLP-1. These results suggest that GLP-1 modulates both excitatory and inhibitory synaptic inputs to pancreas-projecting vagal motoneurons.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.peptides.2007.08.016 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Vagal sensory neuron-derived FGF3 controls insulin secretion.
Dev Cell
January 2025
Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY 01595, USA; Department of Pharmacology, New York Medical College, Valhalla, NY 10595, USA. Electronic address:
Vagal nerve stimulation has emerged as a promising modality for treating a wide range of chronic conditions, including metabolic disorders. However, the cellular and molecular pathways driving these clinical benefits remain largely obscure. Here, we demonstrate that fibroblast growth factor 3 (Fgf3) mRNA is upregulated in the mouse vagal ganglia under acute metabolic stress.
View Article and Find Full Text PDFAcute pancreatitis decreases the sensitivity of pancreas-projecting dorsal motor nucleus of the vagus neurones to group II metabotropic glutamate receptor agonists in rats.
J Physiol
March 2014
Department of Neural and Behavioral Sciences, Penn State College of Medicine, 500 University Drive, MC H109, Hershey, PA 17033, USA.
Recent studies have shown that pancreatic exocrine secretions (PES) are modulated by dorsal motor nucleus of the vagus (DMV) neurones, whose activity is finely tuned by GABAergic and glutamatergic synaptic inputs. Group II metabotropic glutamate receptors (mGluR) decrease synaptic transmission to pancreas-projecting DMV neurones and increase PES. In the present study, we used a combination of in vivo and in vitro approaches aimed at characterising the effects of caerulein-induced acute pancreatitis (AP) on the vagal neurocircuitry modulating pancreatic functions.
View Article and Find Full Text PDFModulation of pancreatic exocrine and endocrine secretion.
Curr Opin Gastroenterol
September 2013
Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.
Purpose Of Review: Recent advances in the regulation of pancreatic secretion by secretagogues, modulatory proteins and neural pathways are discussed.
Recent Findings: Downstream events involved in secretagogue stimulation of pancreatic secretion have been elucidated through characterization of the Src kinase pathway. An additional mechanism regulating vagus nerve effects on the pancreas involves Group II and III metabotropic glutamate receptors that are located presynaptically on certain vagal pancreas-projecting neurons.
Pancreatic insulin and exocrine secretion are under the modulatory control of distinct subpopulations of vagal motoneurones in the rat.
J Physiol
August 2012
Department of Neural and Behavioral Sciences, Penn State College of Medicine, 500 University Drive, MC H109, Hershey, PA 17033, USA.
Brainstem vago-vagal neurocircuits modulate upper gastrointestinal functions. Derangement of these sensory-motor circuits is implicated in several pathophysiological states, such as gastroesophageal reflux disease (GERD), functional dyspepsia and, possibly, pancreatitis. While vagal circuits controlling the stomach have received more attention, the organization of brainstem pancreatic neurocircuits is still largely unknown.
View Article and Find Full Text PDFGlucagon-like peptide-1 modulates synaptic transmission to identified pancreas-projecting vagal motoneurons.
Peptides
November 2007
Research Center of Digestive Diseases, Zhongnan Hospital, Key Laboratory of Allergy and Immune-related Diseases, Department of Physiology, School of Basic Medical Science, Wuhan University, Wuhan, Hubei 430071, PR China.
Using a brainstem slice preparation, we aimed to study the pre- and postsynaptic effects of glucagon-like peptide-1 (GLP-1) on synaptic transmission to identified pancreas-projecting vagal motoneurons. Following blockade of GABAergic mediated currents with bicuculline, perfusion with 100 nM GLP-1 increased both amplitude and frequency of excitatory postsynaptic currents (EPSCs) in 21 of 52 neurons. Perfusion with the GLP-1 selective agonist exendin-4 (100 nM), also increased the frequency of spontaneous EPSCs, while pretreatment with the GLP-1 selective antagonist, exendin 9-39, prevented the effects of GLP-1.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!