Improvement of contextual memory by S 24795 in aged mice: comparison with memantine
- First Online:
In comparison with 5-month-old mice, 18- to 19-month-old mice exhibited a severe and specific memory impairment in a contextual serial discrimination (CSD) task involving the learning and remembering of two successive spatial discriminations carried out on two distinct floors. This impairment was specific, as spatial memory, simultaneously tested on a simple discrimination (SD) task, was not affected in these aged mice. This deficit was completely reversed by 9-day per os administration of S 24795, a partial agonist of α7 nicotinic receptors, at either 0.3 or 1.0 mg/kg. Memantine, an NMDA receptor antagonist, also had a memory-enhancing effect at a dose of 3.0 mg/kg, but not at 0.3 mg/kg.
The memory-enhancing effect of S 24795 was due to a strong enhancement of contextual memory as indicated by a decrease in interference rate, whereas memantine enhanced spatial/semantic memory. S 24795 was more effective than memantine and also appears to be more specific to flexible forms of memory, one of the first cognitive domains (i.e. episodic memory) affected in Alzheimer’s disease.
KeywordsAgeing Mice Contextual memory Episodic memory S 24795 Memantine Nicotinic receptors
- David V, Chauveau F, Pierard C, Beracochea D (2006) Different involvement of the hippocampus and amygdala in the retrieval pattern of serial contextual information after an acute stress in mice. In: FENS Forum Abstracts, vol. 3, Vienna, 8–12 July 2006Google Scholar
- Eichembaum H (2000) A cortical-hippocampal system for declarative memory. Nat Rev Neurosci 2:844–847Google Scholar