Growth hormone replacement in hypophysectomized rats affects spatial performance and hippocampal levels of NMDA receptor subunit and PSD-95 gene transcript levels
| Autor: | Fred Nyberg, Madeleine Le Grevès, Marita Berg, Bengt J. Meyerson, Pierre Le Grevès, Karin Fhölenhag, Qin Zhou |
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| Rok vydání: | 2006 |
| Předmět: |
Male
medicine.medical_specialty Transcription Genetic Hormone Replacement Therapy Hippocampus Morris water navigation task Hippocampal formation Biology Weight Gain Receptors N-Methyl-D-Aspartate Rats Sprague-Dawley Growth factor receptor Memory Internal medicine medicine Animals Receptor Maze Learning Hypophysectomy General Neuroscience Intracellular Signaling Peptides and Proteins Membrane Proteins Long-term potentiation Blotting Northern Rats Endocrinology nervous system Growth Hormone Space Perception Synaptic plasticity NMDA receptor Disks Large Homolog 4 Protein Psychomotor Performance |
| Zdroj: | Experimental brain research. 173(2) |
| ISSN: | 0014-4819 |
| Popis: | Clinical studies have demonstrated that growth hormone (GH) promotes learning and memory processes in GH-deficient (GHD) patients. In animal studies, GH also influences the N-methyl-D-aspartate (NMDA) receptor system in the hippocampus, an essential component of long-term potentiation (LTP), which is highly involved in memory acquisition. This study was designed to examine the beneficial effects of recombinant human GH (rhGH) on cognitive function in male rats with multiple hormone deficiencies resulting from hypophysectomy (Hx). The performance of an rhGH-treated group and an untreated control group was appraised in the Morris water maze (MWM). The rhGH-treated group performed significantly better in the spatial memory task than the control animals on the second and third trial days. Further training eliminated this difference between the groups. Hippocampal mRNA expression of the NMDA subunits NR1, NR2A and NR2B, insulin-like growth factor type 1 receptor (IGF-1R), and postsynaptic density protein-95 (PSD-95) was then measured in the animals by Northern blot analysis. The results suggest that there may be a relationship between the NMDA receptor subunit mRNA expression levels and learning ability, and that learning is improved by rhGH in Hx rats. Furthermore, a link between MWM performance and PSD-95 was also suggested by this study. |
| Databáze: | OpenAIRE |
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