Effect of curcumin on cognitive dysfunction in a rat model of trigeminal neuralgia / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the effect of curcumin on cognitive dysfunction in a rat model of trigeminal neuralgia.Methods Thirty healthy adult male Sprague-Dawley rats,weighing 200-250 g,were randomly divided into 3 groups (n=10 each) using a random number tablesham operation group (Sham group),trigeminal neuralgia group (TN group),and trigeminal neuralgia + curcumin group (TN + Cur group).Trigeminal neuralgia was produced by injecting cobra venom solution 4 μl into the sheath of the infraorbital nerve in TN and TN + Cur groups.Starting from 15 days after establishment of the model,1.5 ml peanut oil was injected through a gastric tube into stomach twice a day (in the morning and at night) for 28 consecutive days in TN group,and curcumin 45 mg/kg (dissolved in 1.5 ml peanut oil) was injected through a gastric tube into stomach twice a day (in the morning and at night) for 28 consecutive days in TN + Cur group.The cognitive function was assessed using Morris water maze test after the end of treatment.The escape latency,swimming speed,ratio of time of staying at the target quadrant,and the number of times the animals crossing the platform were recorded.The pathological changes in the hippocampal CA1 region were observed with an electron microscope.The ultrastructure of neurons,organelles and synapses in the hippocampal CA1 region was examined with a transmission electron microscope.Results There was no significant difference in the swimming speed between the three groups (P＞0.05).Compared with Sham group,the escape latency on 1st-4th days was significantly prolonged,the ratio of time of staying at the target quadrant was decreased,and the number of times the animals crossing the platform was decreased in TN group,and the escape latency was significantly prolonged on 3rd and 4th days in TN + Cur group (P＜0.01).Compared with TN group,the escape latency on 2nd-4th days was significantly shortened,the ratio of time of staying at the target quadrant was increased,the number of times the animals crossing the platform was increased (P＜0.01),and the pathological changes of hippocampal tissues were attenuated in TN + Cur group.Conclusion Curcumin can improve cognitive dysfunction in a rat model of trigeminal neuralgia.