Histological study on the effect of aluminium chloride on frontal cortex of adult male albino rats

ABSTRACT

Several studies implicated aluminium in the pathogenesis of many neurodegenerative disorders especially Alzheimer disease, although the underlying histopathological changes in the brain were not clear with many controversies. So we aimed to elucidate these histological, immunohistochemical and ultrastructural changes that might occur in the rat brain after aluminium exposure. In this study we used 18 adult male albino rats divided into 2 groups; a control group and an experimental group taking 600 mg/ kg aluminium chloride orally daily for 4 weeks. At the end of the fourth week, samples from the frontal cortex were obtained and stained with H and E, and glial fibrillary acidic protein [GFAP]. Other samples were processed for electron microscopic examination. Morphometric study was done for GFAP immunostaining. The group taking 600 mg/ kg aluminium chloride showed decreased body weight and had developed some neurological symptoms. Routine H and E revealed presence of some shrunken pyramidal cells with pyknotic nuclei; immunoreactivity for glial fibrillary acidic protein [GFAP] was decreased compared to control group. Ultrastructurally; some neurons showed shrunken nuclei, swelling and damage of the mitochondria and dilated saccules of Golgi apparatus and endoplasmic reticulum with the appearance of vacuolated areas in the cytoplasm with splitting of myelin sheath and degeneration of some nerve fibres. Aluminium in high doses can cause alterations in neurons and nerve fibers with decreased immunoreactivity for GFAP in astrocytes in the brain, so further studies would be needed to evaluate the effects of chronic exposure in apparently healthy individuals