title: Hippocampal neuronal loss, decreased GFAP immunoreactivity and cognitive impairment following experimental intoxication of rats with aluminum citrate.
abstract: Aluminum (Al) is a neurotoxic agent with deleterious actions on cognitive processes. Nevertheless, few studies have investigated the neuropathological effects underlying the Al-induced cognitive impairment. We have explored the effects of acute Al citrate intoxication on both hippocampal morphology and mnemonic processes in rodents. Adult male Wistar rats were intoxicated with a daily dose of Al citrate (320 mg/kg) during 4 days by gavage. Animals were perfused at 8 (G2), 17 (G3) and 31 days (G4) after intoxication. Control animals were treated with sodium citrate (G1). Animals were submitted to behavioral tests of open field and elevated T-maze. Immunohistochemistry was performed to label neurons (anti-NeuN) and astrocytes (anti-GFAP) in both CA1 and CA3 hippocampal regions. There was an increase in the locomotor activity in open field test for G2 in comparison to control group and other groups (ANOVA-Bonferroni, P<0.05). The elevated T-maze avoidance latency (AL) was higher in all intoxicated groups compared to control (P<0.05) in avoidance 1. These values remained elevated in avoidance 2 (P<0.05), but abruptly decreased in G2 and G3, but not in G1 and G4 animals in avoidance 3 (P<0.05). There were no significant differences for 1 and 2 escape latencies. There were intense neuronal loss and a progressive decrease in GFAP immunoreactivity in the hippocampus of intoxicated animals. The results suggest that Al citrate treatment induces deficits on learning and memory concomitant with neuronal loss and astrocyte impairment in the hippocampus of intoxicated rats.
authors.affiliation: Laboratory of Experimental Neuroprotection and Neuroregeneration, Institute of Biological Sciences, Federal University of Pará, Brazil.
authors.forename: Ademir F Junior
authors.initials: AF
authors.lastname: Silva
authors.forename: Maria Socorro S
authors.initials: MS
authors.lastname: Aguiar
authors.forename: Odemir S Junior
authors.initials: OS
authors.lastname: Carvalho
authors.forename: Luana de Nazaré S
authors.initials: Lde N
authors.lastname: Santana
authors.forename: Edna C S
authors.initials: EC
authors.lastname: Franco
authors.forename: Rafael Rodrigues
authors.initials: RR
authors.lastname: Lima
authors.forename: Natalino Valente M de
authors.initials: NV
authors.lastname: Siqueira
authors.forename: Romulo Augusto
authors.initials: RA
authors.lastname: Feio
authors.forename: Lilian Rosana F
authors.initials: LR
authors.lastname: Faro
authors.forename: Walace
authors.initials: W
authors.lastname: Gomes-Leal
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001007:Anxiety / Q000523:psychology; D001253:Astrocytes / Q000187:drug effects; D001362:Avoidance Learning / Q000187:drug effects; D019343:Citric Acid; D003072:Cognition Disorders / Q000139:chemically induced / Q000473:pathology* / Q000523:psychology; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism*; D006624:Hippocampus / Q000378:metabolism / Q000473:pathology*; D007150:Immunohistochemistry; D007859:Learning Disabilities / Q000139:chemically induced / Q000523:psychology; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008569:Memory Disorders / Q000139:chemically induced / Q000473:pathology; D009043:Motor Activity / Q000502:physiology; D009474:Neurons / Q000378:metabolism / Q000473:pathology*; D020258:Neurotoxicity Syndromes / Q000473:pathology* / Q000523:psychology; D011597:Psychomotor Performance / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D013534:Survival
chemical_list: D005904:Glial Fibrillary Acidic Protein; D019343:Citric Acid; C455846:aluminum citrate