Neuroprotection of Lidocaine by Injecting into Cisterna Magna in a Rabbit Model of Subarachnoid Hemorrhage

Objective To investigate the prevention effect on cerebral vasospasm and hippocampus tissue damage by intracisternal delivery of lidocaine in rabbit model of subarachnoid hemorrhage.Methods Thirty New Zealand white rabbits were randomly allocated to the sham group,subarachnoid hemorrhage group(SAH),and lidocaine therapy group(n=10,respectively).All animals underwent operation under general anaesthesia.1.5 mL autologous nonheparinized arterial blood was injected into cisterna magna in the SAH group and lidocaine group,and 1.5 mL saline into cisterna magna in the sham group respectively.Thirty minutes after SAH,0.1 mL saline was injected into cisterna magna in the sham group and SAH group,and 0.1 mL 2% lidocaine into cisterna magna in the lidocaine group,respectively.72 hours later,all animals were deeply anesthetized and killed by perfusion-fixation.Their basilar arteries and the hippocampus tissue were processed for morphometric analysis.The level of interleukin-6(IL-6) in serum was measured by ELISA pre-operation and at 72 hours after SAH.Results The baseline level of IL-6 was not significantly different in three groups(P0.05).But the level of IL-6 in the SAH group was higher than that of the other groups(P0.05) at 72 hours after SAH.As compared to the baseline,the level of IL-6 was significantly higher in three groups at 72 hours after SAH(P0.05).The cross-section areas and diameter of basal arteries,the normal neuron density of the hippocampus were smaller in SAH group than that of the other two groups(P0.05).The cells of expressing c-fos in the hippocampus tissue were more in SAH group than that of the other groups(P0.05).Conclusions The study indicated that intracisternal administration of lidocaine could prevent the cerebral vasospasm and hippocampus tissue damage in a rabbit model of subarachnoid hemorrhage.