ABSTRACT

Medicinal plants have been used in treatment of various ailments because of the active phytochemicals present in them. One of such plant is tamarindus indica. Several reports have indicated that the phytochemicals in T. indica possesses multifaceted actions, including anti-oxidant, anti-carcinogenic, anti-inflammatory, anti-microbial and anti-diabetic effect amongst others. Mercury chloride is a highly toxic compound, both acutely and as a cumulative poison. Chronic exposure can lead to symptoms more common with mercury poisoning, such as insomnia, delayed reflexes, excessive salivation, bleeding gums, fatigue, tremors, and dental problems. Acute exposure to large amounts of mercuric chloride can cause death in as little as 24 hours. Methylmercury,oneofthecompoundsofmercury,isprimarilyresponsiblefortheneurologicalchangesobservedinlaboratoryanimalsandhumans. Cerebellum is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, it plays an important role in motor control. Cerebellar damage produces disorders in fine movement, equilibrium, posture, and motor learning in humans. This study is aimed at determining the ameliorative effect of tamarindus indica on mercury chloride-induced cerebellar damage in adult wistar rats. Twenty-five (25) adult wistar rats weighing between 181-280g were randomly assigned into five groups (A to E) and everything took thirty days (30) with group (A) containing five rats while group (B-E) containing ten rat each. Group (A) rats (control) received pelletized growing mesh and distilled water, Group (B) received 1ml of mercury chloride only, Group (C) received 500mg/kg body weight of tamarindus indica only, Group (D) received mercury chloride + 250mg/kg body weight of  tamarindus indica, Group (E) received mercury chloride + 500mg/kg body weight of tamarindus indica. After administration, the animals were sacrificed under chloroform anaesthesia, the cerebellum was harvested and fixed in 10% formal saline solution for histological analysis and processed for assays according to the established methods. There was no change on the body weight in the control group when the initial body weight was compared to the final body weight. MDA showed increase in mercury chloride only and 500mg/kg of tamarindus indica only when compared to control group. Gpx showed decrease in mercury chloride only and increase in 500mg/kg of tamarindus indica only when compared to control group. CAT showed increase in mercury chloride only and rats treated with 500mg/kg of Tamarindus indica only when compared with control. SOD showed increase in mercury chloride only when compared with control.Histologically, Group A, C and D showed normal cerebellar tissue with Molecular layer, Purkinje layer and Granular layer with D having visible white matter, Group B exhibited a high level of Cerebellar Oedema and Purkinje axonal degeneration, Group E showed the presence of patchy areas with Cerebellar Oedema, Purkinje and Granular cell degeneration. The results of the biochemical assay were in harmony with that of the histology. In conclusion, aqueous extract of tamarindus indica has an ameliorative effect against mercury chloride-induced cerebellar damage, which was observed by the level of improvement in histological and biochemical markers. It was confirmed the mercury chloride has a pathological effect on the cerebellum of adult whistar rat and aqueous extract of tamarindus indica is more potent at a low dose (250mg/kg) in ameliorating cerebellar damage induced by mercury chloride compare to a high dose.