The presence of perforated synapses in the striatum after dopamine depletion, is this a sign of maladaptive brain plasticity?

Autor:	Anaya-Martínez V; Neuromorphology Lab, Facultad de Estudios Superiores Iztacala, UNAM, Av. de los Barrios 1, Los Reyes Iztacala, Tlalnepantla, Edo. Mex. 54090, Mexico., Gutierrez-Valdez AL; Neuromorphology Lab, Facultad de Estudios Superiores Iztacala, UNAM, Av. de los Barrios 1, Los Reyes Iztacala, Tlalnepantla, Edo. Mex. 54090, Mexico., Ordoñez-Librado JL; Neuromorphology Lab, Facultad de Estudios Superiores Iztacala, UNAM, Av. de los Barrios 1, Los Reyes Iztacala, Tlalnepantla, Edo. Mex. 54090, Mexico., Montiel-Flores E; Neuromorphology Lab, Facultad de Estudios Superiores Iztacala, UNAM, Av. de los Barrios 1, Los Reyes Iztacala, Tlalnepantla, Edo. Mex. 54090, Mexico., Sánchez-Betancourt J; Neuromorphology Lab, Facultad de Estudios Superiores Iztacala, UNAM, Av. de los Barrios 1, Los Reyes Iztacala, Tlalnepantla, Edo. Mex. 54090, Mexico., Sánchez Vázquez del Mercado C; Neuromorphology Lab, Facultad de Estudios Superiores Iztacala, UNAM, Av. de los Barrios 1, Los Reyes Iztacala, Tlalnepantla, Edo. Mex. 54090, Mexico., Reynoso-Erazo L; Health Education Project, Facultad de Estudios Superiores Iztacala, UNAM, Av. de los Barrios 1, Los Reyes Iztacala, Tlalnepantla, Edo. Mex. 54090, Mexico., Tron-Alvarez R; Health Education Project, Facultad de Estudios Superiores Iztacala, UNAM, Av. de los Barrios 1, Los Reyes Iztacala, Tlalnepantla, Edo. Mex. 54090, Mexico., Avila-Costa MR; Neuromorphology Lab, Facultad de Estudios Superiores Iztacala, UNAM, Av. de los Barrios 1, Los Reyes Iztacala, Tlalnepantla, Edo. Mex. 54090, Mexico nigraizo@unam.mx mariarosa@avila-costa.com.
Jazyk:	angličtina
Zdroj:	Microscopy (Oxford, England) [Microscopy (Oxf)] 2014 Dec; Vol. 63 (6), pp. 427-35. Date of Electronic Publication: 2014 Sep 22.
DOI:	10.1093/jmicro/dfu032
Abstrakt:	Synaptic plasticity is the process by which long-lasting changes take place at synaptic connections. The phenomenon itself is complex and can involve many levels of organization. Some authors separate forms into adaptations that have positive or negative consequences for the individual. It has been hypothesized that an increase in the number of synapses may represent a structural basis for the enduring expression of synaptic plasticity during some events that involve memory and learning; also, it has been suggested that perforated synapses increase in number after some diseases and experimental situations. The aim of this study was to analyze whether dopamine depletion induces changes in the synaptology of the corpus striatum of rats after the unilateral injection of 6-OHDA. The findings suggest that after the lesion, both contralateral and ipsilateral striata exhibit an increased length of the synaptic ending in ipsilateral (since third day) and contralateral striatum (since Day 20), loss of axospinous synapses in ipsilateral striatum and a significant increment in the number of perforated synapses, suggesting brain plasticity that might be deleterious for the spines, because this type of synaptic contacts are presumably excitatory, and in the absence of the modulatory effects of dopamine, the neuron could die through excitotoxic mechanisms. Thus, we can conclude that the presence of perforated synapses after striatal dopamine depletion might be a form of maladaptive synaptic plasticity. (© The Author 2014. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
Databáze:	MEDLINE
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