Allium sativum and Vitamin C Co-administration Attenuates Mercuric Chloride-Induced Neurotoxicity in the Prefrontal Cortex in Wistar Rats
The histological and immunohistochemical assessment of the effects of co-administration of Allium sativum ethanolic extract and Vitamin C on the medial prefrontal cortex of mercuric chloride induced neurotoxicity model Wistar rats was investigated. Thirty-five adult Wistar rats weighing 150 - 180 g randomized into 7 groups of 5 animals each were used for this study. Group 1 served as negative control and received 1 ml distilled water daily, group 2 served as positive control and received mercuric chloride 49.8 mg/kg body weight, group 3 received Allium sativum ethanolic extract 500 mg/kg body weight. Groups 4, 5, 6 and 7 were initially administered with mercuric chloride 49.8 mg/kg body weight, and treated for 14 days with Allium sativum 250 mg per kg body weight, Vitamin C 100 mg per kg body weight, Allium sativum 250 mg + Vitamin C 100 mg per kg body weight, and Allium sativum 500 mg + Vitamin C 100 mg per kg body weight respectively. Administrations were by orogastric intubation. Twenty-four hours after the last treatment, the rats were sacrificed under chloroform anaesthetic. The brains were harvested, processed for histological studies using H&E for general morphology, Cresyl fast violet for Nissl substance and immunohistochemical method for glial fibrillary acidic protein (GFAP) antibody expression. Results of H&E sections indicated intact pyramidal and granule cells of the prefrontal cortex in groups 6 and 7 compared to group 2. Nissl substance expression was higher in combined treated groups 6 and 7 compared to groups 3 and 4. GFAP-immunopositive astrocytes was mild in combined treated group compared to groups 2, 3 and 4. In conclusion combined administration of ethanolic extract of A. sativum and Vitamin C reduced the damaging effects of mercuric chloride on the medial prefrontal cortex of the Wistar rats.
Key Words: mercuric chloride; Allium sativum; vitamin C; prefrontal cortex; histology