Somatostatin triggers rhythmic electrical firing in hypothalamic GHRH neurons
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Published version
Author(s)
Type
Journal Article
Abstract
Hypothalamic growth hormone-releasing hormone (GHRH) neurons orchestrate body growth/maturation and have been implicated in feeding responses and ageing. However, the electrical patterns that dictate GHRH neuron functions have remained elusive. Since the inhibitory neuropeptide somatostatin (SST) is considered to be a primary oscillator of the GH axis, we examined its acute effects on GHRH neurons in brain slices from male and female GHRH-GFP mice. At the cellular level, SST irregularly suppressed GHRH neuron electrical activity, leading to slow oscillations at the population level. This resulted from an initial inhibitory action at the GHRH neuron level via K+ channel activation, followed by a delayed, sst1/sst2 receptor-dependent unbalancing of glutamatergic and GABAergic synaptic inputs. The oscillation patterns induced by SST were sexually dimorphic, and could be explained by differential actions of SST on both GABAergic and glutamatergic currents. Thus, a tripartite neuronal circuit involving a fast hyperpolarization and a dual regulation of synaptic inputs appeared sufficient in pacing the activity of the GHRH neuronal population. These “feed-forward loops” may represent basic building blocks involved in the regulation of GHRH release and its downstream sexual specific functions.
Date Issued
2016-04-13
Date Acceptance
2016-03-29
Citation
Scientific Reports, 2016, 6
ISSN
2045-2322
Publisher
Nature Publishing Group
Journal / Book Title
Scientific Reports
Volume
6
Copyright Statement
This work is licensed under a Creative Commons Attribution 4.0 International License. The images
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unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license,
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or other third party material in this article are included in the article’s Creative Commons license,
unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license,
users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/
License URL
Sponsor
Diabetes UK
European Foundation for the Study of Diabetes
Grant Number
15821
N/A
Subjects
Science & Technology
Multidisciplinary Sciences
Science & Technology - Other Topics
GROWTH-HORMONE-SECRETION
HEPATIC-STEROID METABOLISM
PROTEIN TRANSGENIC MICE
NETWORK MOTIFS
IN-VITRO
PARAVENTRICULAR NUCLEUS
RECEPTOR SUBTYPES
SEXUAL-DIMORPHISM
MODEL
EXPRESSION
Publication Status
Published
Article Number
24394