NEUROCHEMISTRY

Author: MARTÍNEZ VILLAYANDRE BEATRIZ.
Year: 2004.
University: LEÓN [www.unileon.es].
Place of defense: FACULTAD DE VETERINARIA.
Place of preparation: FACULTAD DE VETERINARIA.

Summary: The objective of this work was a study on the role of NMDA receptor in the process of aging. The existence of previous data indicating that existed during aging hipofunción glutamatergic mediated receptor ionotrópicos, particularly by the NMDA receptor and that the process of aging, which the diet could play a key role, accelerated in states with oxidative imbalance a concomitant increase of free radicals, led to the following conditions arise study: a control group fed a standard diet, a second group, which would induce oxidative stress through the administration of acid d-aminolevulínico and a third group , which is provide vitamin E as an antioxidant agent. The study was conducted with rats three different ages: 4, 12 and 24 months, which correspond to young adults and middle aged, respectively, and using techniques marked radioligandos and antibodies. Specifically, the proposed objectives were as follows: Study by NMDA receptor binding test membranes, using as radioligando [3H] MK - 801, at different stages of aging and after chronic treatment with an agent or prooxidante an antioxidant; survey of the distribution autoradiographic NMDA receptor, using the same radioligando indicated in the above objective, determination of fixing radioligando to NMDA receptors through studies autorradiográficos at different stages of aging and after treatments above and study of the an expression of the subunit NR2A receptor NMDA by Western blot studies, in different stages of aging and the different experimental conditions. The conclusions obtained in this study were as follows: * In rats, there was a decrease in the density of NMDA receptors linked to age in the cerebral cortex and in the striated. However, the levels of NMDA receptors in the hippocampus are less age-related changes in the structures mentioned above, at least up to 24 months. Moreover, the receptor subunit NR2A in the subject of study does not seem sugrir modifications age-dependent, at least up to 24 months. * The chronic treatment with the oxidizing acid d-aminolevulínico, induces a down-regulation of NMDA receptors independent of age, cortex, hippocampus and striped. In the cerebral cortex, the subunit NR2A contributed to the declines of NMDA receptors induced by treatment with ALA. * Treatment with the antioxidant vitamin E agent is capable of producing a up-regulation of NMDA receptors in cortex. Hippocampus and striped, independently of age. Changes in NMDA receptor induced by the tratamietno with vitamin E did not affect their subunit NR2A. * Treatments oxidant and antioxidant agents studied, suggesting that changes to the NMDA receptors are dependent oxidative stress.