Early systemic administration of erythropoietin partially relieves cerebral vasospasm after subarachnoid hemorrhage in rabbits

Abstract

Objective To study the effect of carry systemic administration of erythropoietin (EPO)on cerebral vasospasm(cvs)after subarachnoid hemorrhage(SAH)and explore the possible mechanism. Methods Thirty male New Zealand rabbits were randomized equally into 5 groups.namely the blank control group, saline group,SAH model group,SAH+placebo group,and SAH+recombinant human erythropoietin(rHuEPO)group.In the latter 3 groups,rabbit SAH model was established by autologous blood injection into the cisterna magna,and in the saline group,only normal saline was injected.Fiveminutes after the blood injeetion,the rabbits received intraperitoneal injection of rHuEPO or placebo(EPO solvent)as indicated,followed by another 5 injections at the interval of8 h.Forty-eighthours after the model establishment,the rabbits were sacrificed by perfusion-fixation and the basiiar army Was taken.The cross-sectional area of the lumen of the basllar artery Was measured to evaluate the degree of cerebral vasospasm.TUNEL assay was used to detect endothelial cell apoptosis in the basilar artery. Results The average cross-sectional area of the basilar arteries showed no significant difference between the blank control and the saline groups or between SAH and SAH+placebo groups(P>0.05).The cross-sectional area of the basilar artery in SAH+rHuEPO group was significantly greater than that in SAH group and SAH+placebo group(P<0.05),but smaller than that in the blank control and saline groups.TUNEL assay revealed less intense apoptosis of the endothelial cells in SAH+rHuEPO group than in SAH group or SAH+placebo group(P0.05).Conclusion Early systemic administration of rHuEPO can decrease endothelial cell apoptosis in the basilar artery and may partially attenuate the intensity of CVS in rabbits with SAH. Key words: Subarachnoid hemorrhage; Cerebral vasospasm; Erythropoietin; Apoptosis