Cognitive deficits in adult rats by lead intoxication are related with regional specific inhibition of cNOS
Por:
García-Arenas G., Ramírez-Amaya V., Balderas I., Sandoval J., Escobar M.L., Ríos C., Bermúdez-Rattoni F.
Publicada:
1 ene 2004
Resumen:
It is well known that lead can affect several cognitive abilities in developing animals. In this work, we investigate the effects of different sub-chronic lead doses (0, 65, 125, 250 and 500ppm of lead acetate in their drinking water for 14 days) in the performance of male adult rats in a water maze, cue maze and inhibitory avoidance tasks. We found that the acquisition of these tasks was not affected by lead, however, the highest dosage of lead (500ppm) impaired memory consolidation in spatial and inhibitory avoidance tasks, but not in cue maze task while the 250ppm dose only affected retrieval of spatial memory. Additionally, hippocampal long-term potentiation (LTP) induction in the perforant path after exposing adult rats to different doses of lead was studied. LTP induction was affected in a dose-dependent manner, and treatments of 250 and 500ppm completely blocked LTP. We investigated the effects of lead intoxication on the activity of constitutive nitric oxide synthase (cNOS) in different brain regions of adult animals. The activity of cNOS was significantly inhibited in the hippocampus and cerebellum but not in the frontal cortex and brain stem, although lead had accumulated in all brain regions. These results suggest that lead intoxication can impair memory in adult animals and this impairment might be related with region-specific effects on cNOS activity. © 2003 Elsevier B.V. All rights reserved.
Filiaciones:
García-Arenas G.:
Centro Nacional de Salud Ambiental, Area Toxicol. Ambiental Inst. N., SSA, Mexico, Mexico
Ramírez-Amaya V.:
Departamento de Neurociencias, Inst. de Fisiología Celular, Univ. Nac. Auton. de México, Apartado Postal 70-253, 04510 Mexico, Mexico
Balderas I.:
Departamento de Neurociencias, Inst. de Fisiología Celular, Univ. Nac. Auton. de México, Apartado Postal 70-253, 04510 Mexico, Mexico
Sandoval J.:
Departamento de Neurociencias, Inst. de Fisiología Celular, Univ. Nac. Auton. de México, Apartado Postal 70-253, 04510 Mexico, Mexico
Escobar M.L.:
Div. de Invest. y Posgrado, Facultad de Psicología, UNAM, Mexico, Mexico
Ríos C.:
Departamento de Neuroquímica, Inst. Nac. de Neurol. y Neurocirugia, Mexico, Mexico
Bermúdez-Rattoni F.:
Departamento de Neurociencias, Inst. de Fisiología Celular, Univ. Nac. Auton. de México, Apartado Postal 70-253, 04510 Mexico, Mexico
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