Bombesin facilitates GABAergic transmission and depresses epileptiform activity in the entorhinal cortex
- PMID: 23966303
- DOI: 10.1002/hipo.22191
Bombesin facilitates GABAergic transmission and depresses epileptiform activity in the entorhinal cortex
Abstract
Bombesin and the bombesin-like peptides including neuromedin B (NMB) and gastrin-releasing peptide (GRP) are important neuromodulators in the brain. We studied their effects on GABAergic transmission and epileptiform activity in the entorhinal cortex (EC). Bath application of bombesin concentration-dependently increased both the frequency and amplitude of sIPSCs recorded from the principal neurons in the EC. Application of NMB and GRP exerted the same effects as bombesin. Bombesin had no effects on mIPSCs recorded in the presence of TTX but slightly depressed the evoked IPSCs. Omission of extracellular Ca(2+) or inclusion of voltage-gated Ca(2+) channel blockers, Cd(2+) and Ni(2+), blocked bombesin-induced increases in sIPSCs suggesting that bombesin increases GABA release via facilitating extracellular Ca(2+) influx. Bombesin induced membrane depolarization and slightly increased the input resistance of GABAergic interneurons recorded from layer III of the EC. The action potential firing frequency of the interneurons was also increased by bombesin. Bombesin-mediated depolarization of interneurons was unlikely to be mediated by the opening of a cationic conductance but due to the inhibition of inward rectifier K(+) channels. Bath application of bombesin, NMB and GRP depressed the frequency of the epileptiform activity elicited by deprivation of Mg(2+) from the extracellular solution suggesting that bombesin and the bombesin-like peptides have antiepileptic effects in the brain.
Keywords: IPSC; K+ channels; action potential; depolarization; hippocampus; peptide; synaptic transmission.
Copyright © 2013 Wiley Periodicals, Inc.
Similar articles
-
Dopaminergic modulation of GABAergic transmission in the entorhinal cortex: concerted roles of α1 adrenoreceptors, inward rectifier K⁺, and T-type Ca²⁺ channels.Cereb Cortex. 2014 Dec;24(12):3195-208. doi: 10.1093/cercor/bht177. Epub 2013 Jul 10. Cereb Cortex. 2014. PMID: 23843440 Free PMC article.
-
Modulation of GABAergic transmission by muscarinic receptors in the entorhinal cortex of juvenile rats.J Neurophysiol. 2009 Aug;102(2):659-69. doi: 10.1152/jn.00226.2009. Epub 2009 Jun 3. J Neurophysiol. 2009. PMID: 19494196 Free PMC article.
-
Distinct modes of modulation of GABAergic transmission by Group I metabotropic glutamate receptors in rat entorhinal cortex.Hippocampus. 2010 Aug;20(8):980-93. doi: 10.1002/hipo.20697. Hippocampus. 2010. PMID: 19739246 Free PMC article.
-
Comparison of the effects of serotonin in the hippocampus and the entorhinal cortex.Mol Neurobiol. 1998 Winter;17(1-3):59-72. doi: 10.1007/BF02802024. Mol Neurobiol. 1998. PMID: 9887446 Review.
-
GABAergic Synchronization in Epilepsy.Cold Spring Harb Perspect Med. 2016 Jan 8;6(2):a022764. doi: 10.1101/cshperspect.a022764. Cold Spring Harb Perspect Med. 2016. PMID: 26747834 Free PMC article. Review.
Cited by
-
Roles of K+ and cation channels in ORL-1 receptor-mediated depression of neuronal excitability and epileptic activities in the medial entorhinal cortex.Neuropharmacology. 2019 Jun;151:144-158. doi: 10.1016/j.neuropharm.2019.04.017. Epub 2019 Apr 15. Neuropharmacology. 2019. PMID: 30998945 Free PMC article.
-
Inhibition of L-Type Ca2+ Channels by TRPC1-STIM1 Complex Is Essential for the Protection of Dopaminergic Neurons.J Neurosci. 2017 Mar 22;37(12):3364-3377. doi: 10.1523/JNEUROSCI.3010-16.2017. Epub 2017 Mar 3. J Neurosci. 2017. PMID: 28258168 Free PMC article.
-
Synaptic Conductances during Interictal Discharges in Pyramidal Neurons of Rat Entorhinal Cortex.Front Cell Neurosci. 2016 Oct 13;10:233. doi: 10.3389/fncel.2016.00233. eCollection 2016. Front Cell Neurosci. 2016. PMID: 27790093 Free PMC article.
-
Activation of neurotensin receptor 1 facilitates neuronal excitability and spatial learning and memory in the entorhinal cortex: beneficial actions in an Alzheimer's disease model.J Neurosci. 2014 May 14;34(20):7027-42. doi: 10.1523/JNEUROSCI.0408-14.2014. J Neurosci. 2014. PMID: 24828655 Free PMC article.
-
Histamine facilitates GABAergic transmission in the rat entorhinal cortex: Roles of H1 and H2 receptors, Na+ -permeable cation channels, and inward rectifier K+ channels.Hippocampus. 2017 May;27(5):613-631. doi: 10.1002/hipo.22718. Epub 2017 Feb 28. Hippocampus. 2017. PMID: 28188663 Free PMC article.
Publication types
MeSH terms
Substances
Grants and funding
LinkOut - more resources
Full Text Sources
Other Literature Sources
Miscellaneous