Neurobehavioral effects of aluminum exposure in adult female rats

Abstract

Human aluminum exposure is escalating gradually. Aluminum, being a ubiquitous metal, is quite neurotoxic in nature and can easily access the brain through all the stages of life, from fetal to old age, while it’s zillion forms makes its presence in the brain inescapable. The main aim of this research was to investigate if, a relatively lower dose of aluminum could produce inimical effects on the cognitive functions of adult female rats, targeting the two main regions of brain i.e. hippocampus and cortex and to probe into the consequences of Al on spatial learning and memory in rats. The current study also intended to reveal the outcomes of Al intoxication on normal architecture of cortex and hippocampus and permeability of blood brain barrier. The test subjects were fractured into four groups i.e. control group, exposure group and two recoveries were used, recovery 20 days and recovery 40 days to elucidate whether or not recovery plays a role in amelioration of the neurotoxic effect of Al. Female rats were exposed to aluminum mixed in drinking water and after completion of treatment their learning and memory was tested using open field, elevated plus maze and y- maze test paradigms and collated with the controls. The animals from treated and the recovery groups and their controls were euthanized and dissected after the behavioral tests and the brains were removed to extract hippocampus and cortex for further histological and neurochemical analysis. The results unfolded that rats treated with aluminum exhibited significant working and reference memory impairment, elevated anxiety and truncated locomotory and exploratory drive. Histologically, the Al treatment altered the normal architecture of the brain hippocampus and cortex in the exposure group.Neurochemically, Al exposure compromised the intactness of blood brain barrier (BBB), increasing the permeability of BBB relative to the controls. Both the recovery groups showed slight improvement in the neurotoxic effects of Al. To cap it all, this study demonstrates that animals exposed to aluminum show marked deterioration in their cognitive functions and memory and also alters the morphology of the main targeted parts of brain, cortex and hippocampus and may induce irreversible damage to the brain regions.