Evaluation of Chronic Administration of Metronidazole on the Morphological and Biochemical Parameters on the Cerebral Cortex of Adult Wistar Rats

Abstract

Metronidazole has been implicated in diverse neurologic syndromes such as; cerebellar syndrome, encephalopathy, seizures, optic neuropathy, autonomic neuropathy and peripheral neuropathy.  Metronidazole is an antibiotic drug used to treat infections of the reproductive system, gastrointestinal tract, skin, heart, bone joint, lung, blood, nervous system and sexually transmitted diseases (STDs). This study therefore, investigated the effects of metronidazole on the cerebral cortex of adult wistar rats. Thirty-two (32) adult wistar rats of average weight of 180g of both sexes were distributed into four groups of eight (8) animals per group. Group A was the control group while group B, C and D rats were treated with 250 mg/kg, 500 mg/kg and 1000 mg/kg of metronidazole respectively. Metronidazole was administered orally on daily basis to the animals for 28 days. The weights of the rats were taken weekly using a weighing scale. On the 28th day of the treatment, the animals were sacrificed by cervical dislocation. The skulls were excised and the brains were harvested, weighed immediately using a sensitive weighing balance and then fixed in 10% formolcalcium for routine histological techniques and the other parts were processed for biochemical analysis of Malondialdehyde (MDA), Nitric Oxide (NO) and Succinate dehydrogenase (SDH). The results showed that there was a significant increase in the body weights of wistar rats in A and B while the mean body weights of the wistar rats reduced significantly in group C and D. The brain weights in group B and C increased insignificantly while brain weight in group D increased significantly when compared with group A. The biochemical analysis showed significant increase (P<0.05) in the level of MDA, NO and SDH in group B, C and D as compared with group A. Histological study of the cerebral cortex revealed conspicuous degenerative changes in group B while group C and D showed increased degenerative cerebral cortical layers with peripheral and central degenerative changes. The study concluded that metronidazole exhibited a neurodegenerative effect on the cerebral cortex of the wistar rats investigated. It is recommended that other studies should be carried out to corroborate these findings.