Neurodegenerative Observations on the Cerebral Cortex of Adult Wistar Rats Following Mercury Chloride Induced Cortical Damage in Adult Wistar Rats

Main Article Content

A. J. Ajibade
P. B. Fakunle
T. S. Owolabi

Abstract

Background: Mercury is a widespread environmental and industrial pollutant that is used in food preservation, cosmetics, pharmaceutical companies and laboratories. The aim of this present study was to investigate the possible effects of mercury chloride (HgCl2) exposure on the cerebral cortex of adult wista rats; and also to evaluate the effects of mercury on biochemical parameters.

Materials and Methods: Thirty six (36) adult wistar rats of both sexes, weighing between 110 g-300 g were randomly divided into four groups A, B, C and D with nine animals per group. The animals in groups B, C, and D were administered mercury chloride orally at the concentration of 0.2 mg/kg, 0.4mg and 0.5 mg/kg body weights respectively while group (A) served as control and was given distilled water. The administration lasted for a period of 21 days.  The brain was carefully removed and weigh immediately with sensitive balance, part of it was homogenized for biochemical analysis (MDA, GSH and NO). The remaining part was then fixed in 10% formol calcium fluid and processed for histopathological studies using H and E stains.

Results: The results revealed a decrease in animal body weights from all the groups in comparison with the control group (A) which showed an insignificant decrease (P>0.05), group B showed an insignificant decrease (P>0.05) while group C and D showed statistically significant decrease (P<0.05). The brain weights revealed statistically insignificant decrease in the treated groups when compared with the control group. The biochemical evaluation revealed a statistically significant increase (P<0.05) in the level of MDA (Malondialdehyde) in the treated groups when compared with the control group, GSH (Glutathione) revealed statistically significant decrease (P<0.05) in the treated groups and NO (Nitric Oxide) revealed statistically significant increase (P<0.05) in the treated groups as compared to the control group. The histological observation revealed degenerative changes in the cortex of treated groups that were characterized by clustered Pyknotics pyramidal neurons that appear with fragmented cytoplasm and condensed nuclei within soma. Perineural spaces were seen surrounding degenerating neurons. Axons and dendrites are scarcely appreciable around neurons in these groups.

Conclusion:  The findings from this study showed that ingestion of mercury chloride has potentially deleterious effects on brain as shown in the histopathology, cellular loss in the brain of wistar rat.

Keywords:
Mercury, cerebral cortex, degenerative changes, pyramidal neurons.

Article Details

How to Cite
Ajibade, A. J., Fakunle, P. B., & Owolabi, T. S. (2021). Neurodegenerative Observations on the Cerebral Cortex of Adult Wistar Rats Following Mercury Chloride Induced Cortical Damage in Adult Wistar Rats. Asian Journal of Medicine and Health, 18(12), 7-16. https://doi.org/10.9734/ajmah/2020/v18i1230280
Section
Original Research Article

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