The effect of allopurinol on focal cerebral ischaemia: an experimental study in rabbits

In this experimental study, the neuroprotective effect of the xanthine oxidase inhibitor allopurinol on focal cerebral ischaemia created by permanent middle cerebral artery occlusion (MCAO) was investigated. Using high performance liquid chromatography (HPLC), we measured hypoxanthine, xanthine, and uric acid (UA) levels in rabbit brains following focal cerebral ischaemia. Rabbits were randomly and blindly assigned into four groups of eight animals each. The control groups received 2% carboxymethylcellulose solution, while 10% allopurinol 150 mg/kg was given to the treatment group 1 h before ischaemia. Each group was subdivided into two groups which were sacrificed 4 h or 24 h after ischaemia, respectively. UA and xanthine values of the rabbits in the control groups were quite high at both times and highest after 24 h, particularly in the centre of the ischaemia. A significant decrease in UA and xanthine values was observed in rabbits that were given allopurinol (P<0.05). According to our results, it was concluded that allopurinol pretreatment protects neural tissue in the early period after arterial occlusion and prevents cerebral injury in the late period, especially in the perifocal area, possibly by preventing the formation of free radicals with xanthine oxidase inhibition.