Chronic intracerebroventricular infusion of nerve growth factor improves recognition memory in the rat.
Nerve Growth Factor (NGF) plays pivotal roles in neuronal survival in the adult mammalian brain and may modulate forms of structural and functional plasticity, including neurogenesis. We have shown previously that six weeks of housing in an enriched environment (EE) that did not include access to running wheels resulted in improved recognition memory concomitant with increased NGF expression and neurogenesis in the hippocampus. Here we have attempted to probe a causal link between NGF and the observed enrichment-induced changes in hippocampal function by assessing the effects of six weeks continuous intracerebroventricular (i.c.v.) infusion of NGF on recognition memory and cell proliferation. We report that NGF-infused rats show enhanced recognition memory when compared with vehicle-treated controls. Expression of NGF and its receptor, TrkA, was increased in treated rats, as was expression of the synaptic vesicle protein, synapsin. Finally, we observed an increase in cell proliferation in the dentate gyrus of NGF-treated rats. These data indicate that chronic infusion of NGF can stimulate an improvement in learning and memory that is associated with specific cellular changes in the hippocampus, including synaptogenesis and cell proliferation.
Department of Physiology, School of Medicine, Trinity College Institute of Neuroscience, University of Dublin, Trinity College, Dublin 2, Ireland.
Amy M
AM
Birch
Department of Physiology, School of Medicine, Trinity College Institute of Neuroscience, University of Dublin, Trinity College, Dublin 2, Ireland. Electronic address: aikelly@tcd.ie.
Áine M
ÁM
Kelly
D000818:Animals; D004334:Drug Administration Schedule; D016503:Drug Delivery Systems; D005106:Exploratory Behavior / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects; D007276:Injections, Intraventricular; D008297:Male; D020932:Nerve Growth Factor / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D020917:Receptor, trkA / Q000235:genetics / Q000378:metabolism; D021641:Recognition, Psychology / Q000187:drug effects*; D016704:Synapsins / Q000235:genetics / Q000378:metabolism; D016708:Synaptophysin / Q000378:metabolism; D013997:Time Factors
D012333:RNA, Messenger; D016704:Synapsins; D016708:Synaptophysin; D020932:Nerve Growth Factor; D020917:Receptor, trkA
Dentate gyrus; Learning and memory; Nerve growth factor; Neurogenesis; Synaptogenesis