Synapse Plasticity in Motor, Sensory, and Limbo-Prefrontal Cortex Areas as Measured by Degrading Axon Terminals in an Environment Model of Gerbils (Meriones unguiculatus)

• Published in: Journal of neural transplantation & plasticity Vol. 2009; no. 2009; pp. 23 - 36
• Main Authors: Winter, York, Teuchert-Noodt, Gertraud, Grafen, Keren, Witte, A. Veronica, Neufeld, Janina
• Format: Journal Article
• Language: English
• Published: Cairo, Egypt Hindawi Limiteds 01.01.2009; Hindawi Puplishing Corporation; Hindawi Publishing Corporation; John Wiley & Sons, Inc; Hindawi Limited
• Subjects: Analysis of Variance; Animals; Axons; Axons - physiology; Brain; Cerebral Cortex - cytology; Cerebral Cortex - physiology; Environment; Gerbillinae; Gerbils; Housing, Animal; Limbic System - cytology; Limbic System - physiology; Lysosomes - physiology; Male; Meriones unguiculatus; Motor Cortex - cytology; Motor Cortex - physiology; Neuronal Plasticity - physiology; Neurons - cytology; Neurons - physiology; Neuroplasticity; Physiological aspects; Prefrontal Cortex - cytology; Prefrontal Cortex - physiology; Presynaptic Terminals - physiology; Remodeling and renovation; Somatosensory Cortex - cytology; Somatosensory Cortex - physiology; Synapses; Synapses - physiology; Germany
• ISSN: 0792-8483; 2090-5904; 1687-5443
• DOI: 10.1155/2009/281561

Still little is known about naturally occurring synaptogenesis in the adult neocortex and related impacts of epigenetic influences. We therefore investigated (pre)synaptic plasticity in various cortices of adult rodents, visualized by secondary lysosome accumulations (LA) in remodeling axon terminals. Twenty-two male gerbils from either enriched (ER) or impoverished rearing (IR) were used for quantification of silver-stained LA. ER-animals showed rather low LA densities in most primary fields, whereas barrel and secondary/associative cortices exhibited higher densities and layer-specific differences. In IR-animals, these differences were evened out or even inverted. Basic plastic capacities might be linked with remodeling of local intrinsic circuits in the context of cortical map adaptation in both IR- and ER-animals. Frequently described disturbances due to IR in multiple corticocortical and extracortical afferent systems, including the mesocortical dopamine projection, might have led to maladaptations in the plastic capacities of prefronto-limbic areas, as indicated by different LA densities in IR- compared with ER-animals.