Growth hormone modulates hippocampal excitatory synaptic transmission and plasticity in old rats

Date
2012
Advisor
Instructor
Source Title
Neurobiology of Aging
Print ISSN
0197-4580
Electronic ISSN
Publisher
Elsevier
Volume
33
Issue
9
Pages
1938 - 1949
Language
English
Type
Article
Journal Title
Journal ISSN
Volume Title
Abstract

Alterations in the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptor (AMPA-R) and N-methyl-D-aspartate receptor (NMDA-R) have been documented in aged animals and may contribute to changes in hippocampal-dependent memory. Growth hormone (GH) regulates AMPA-R and NMDA-R-dependent excitatory transmission and decreases with age. Chronic GH treatment mitigates age-related cognitive decline. An in vitro CA1 hippocampal slice preparation was used to compare hippocampal excitatory transmission and plasticity in old animals treated for 6-8 months with either saline or GH. Our findings indicate that GH treatment restores NMDA-R-dependent basal synaptic transmission in old rats to young adult levels and enhances both AMPA-R-dependent basal synaptic transmission and long-term potentiation. These alterations in synaptic function occurred in the absence of changes in presynaptic function, as measured by paired-pulse ratios, the total protein levels of AMPA-R and NMDA-R subunits or in plasma or hippocampal levels of insulin-like growth factor-I. These data suggest a direct role for GH in altering age-related changes in excitatory transmission and provide a possible cellular mechanism through which GH changes the course of cognitive decline. © 2012 Elsevier Inc.

Course
Other identifiers
Book Title
Keywords
Long-term potentiation, Paired-pulse ratios, Input-output curves, AMPA receptor, NMDA receptor
Citation
Published Version (Please cite this version)