Tramadol and Coffee Synergy Triggered Oxidative Stress, Altered Cerebellar Histomorphology and Behaviour in Rats

Tramadol intoxication with other substances has recently raised neurological concerns especially among youths in the society. The effects of tramadol and coffee on the cerebellum of Wistar rats were studied. Thirty adult Wistar rats (average weight of 180 g) were randomly assigned into six groups (n=6) as follows: Control, coffee (72.46 mg/kg), coffee (108.69 mg/kg), tramadol (2.86 mg/kg), tramadol (5.71 mg/kg) and coffee (72.46 mg/kg) + tramadol (2.86 mg/kg). The administrations were orally, and done once daily for twenty-eight consecutive days. On day 29, spontane-ous alternation in the T-maze was carried out, and the rats anaesthetized with ketamine hydrochloride (50 mg/kg intraperitoneally). Their blood were assayed for antioxidant, while the 10 % buffered formalin perfused brains were routinely processed with haematoxylin and eosin technique. Behavioural study showed significantly (p<0.05) increased spontaneous alternation in coffee (108.69 mg/kg), tramadol (5.71 mg/kg), and coffee (72.46 mg/kg) + tramadol (2.86 mg/kg) groups compared to the control. Catalase, superoxide dismutase and reduced glutathione levels were not different (p>0.05), while the malondialdehyde level was significantly (p<0.05) higher in the coffee (72.46 mg/kg) + tramadol (2.86 mg/kg) group compared to the control. Histological observations showed cerebellar cytoarchitectural alterations, including atrophy of the Purkinje cells in the coffee (108.69 mg/kg), tramadol (5.71 mg/kg), and coffee (72.46 mg/kg) + tramadol (2.86 mg/kg) groups compared to the control. In conclusion, co-administration of tramadol and coffee triggered free radicals, damaged the cerebellar tissues and caused a more deleterious effect on memory function than individual doses.