Abstract :
Lead is considered as one of the most poisonous heavy metals for humans and animals. Cerebellar Purkinje cells are the most sensitive elements to oxidative stress caused by lead toxicity. The aim of the study was to illustrate the effect of lead and its withdrawal on cerebellar morphology to elucidate a pathological basis of cerebellar dysfunction by representing histopathological, inflammatory immune-cytochemical and electron microscopic (E/M) changes. Fifteen healthy adult male albino rats were used. They divided into three groups (group I: control group, group II: lead acetate injected group, and group III: recovery group). Rats were sacrificed; the cerebellum was removed. Haematoxylin and eosin, immunohistochemical sections, and E/M sections were prepared. Quantitative histomorphometeric estimation was done. Light microscopic examination revealed destruction of cerebellar grey matter cells especially Purkinje cells and distortion of the white matter of group II. Glial fibrillary acidic protein(GFAP) and Cyclo-oxigenase2 (COX2) immunostaining revealed reactive gliosis and inflammatory changes. Statistical analysis revealed increase in mean area percent of GFAP and COX2 sections in molecular and granular layers, respectively. E/M examination displayed distortion of all cerebellar layers. Group III revealed partial recovery of cerebellar structure as well as mild GFAP and COX2 immunoreactions. Significant decrease in mean area percent of GFAP and COX2 sections was detected. E/M inspection of cerebellar grey matter cells showed intact organelles and myelinated axons. This study proved the deleterious effects of lead on rat cerebellum especially on Purkinje cell layer. Withdrawal of lead improved these effects.
