不同浓度氧合血红蛋白对大鼠蛛网膜下腔出血后迟发性脑血管痉挛的影响

The Effect of Oxyhemoglobin in Delayed Cerebral Vasospasm after Subarachnoid Hemorrhage in Rats

目的观察不同浓度氧合血红蛋白对大鼠蛛网膜下腔出血(subarachnoid hemorrhage,SAH)后迟发性脑血管痉挛(delayed cerebral vasospasm,DCV)的影响。方法将24只大鼠分为三组,对照组(8例)、动脉血SAH组(8例)、静脉血SAH组(8例),分别用枕大池二次注血法将0.3 mL生理盐水、自体动脉血、静脉血注入枕大池内,模拟SAH。7 d后处死大鼠,观察脑组织肿胀情况及基底动脉周围血凝块情况,采用HE及免疫荧光染色观察基底动脉形态(管径面积和管壁厚度),电镜下观察基底动脉的超微结构变化。结果动脉血和静脉血SAH组脑组织肿胀、基底动脉周围可见不同程度的血凝块。光镜下,与对照组相比,动脉血和静脉血SAH组管径面积缩小、管壁增厚;与静脉血SAH组相比,动脉血SAH组基底动脉管径面积明显缩小(40816.09±10410.51 nm^(2) vs 68480.89±12687.4 nm^(2),P<0.001),管壁厚度明显增加(3.07±0.59μm vs 2.36±0.25μm,P=0.007)。电镜下,动脉血和静脉血SAH组均出现平滑肌细胞排列紊乱和内皮细胞空泡变性,与静脉血SAH组相比,动脉血SAH组内皮细胞空泡变性更严重,平滑肌细胞排列更加紊乱。结论用自体动、静脉血可以模拟不同浓度氧合血红蛋白引起的SAH后DCV,降低氧合血红蛋白浓度能够减轻SAH后DCV。

Objective To observe the effect of different concentrations of oxyhemoglobin on delayed cerebral vasospasm(DCV)after subarachnoid hemorrhage(SAH)in rats.Methods 24 Sprague-Dawley(SD)rats were divided into three groups:control group(n=8),arterial blood SAH group(n=8)and venous blood SAH group(n=8).SAH models were established by the following methods:0.3 mL normal saline,0.3 mL autogenous arterial blood and 0.3 mL autogenous venous blood were injected into the cisterna magna with double injection of blood,respectively.After 7 days,the swelling and blood clots around basilar arteries,wall area and wall thickness of basilar artery,and the ultrastructural changes were observed among the three groups.Results Some blood clots around basilar arteries and brain swelling were observed in arterial and venous blood SAH groups.Under the light microscope,compared with the control group,basilar artery wall area was reduced and vessel wall was thickened in arterial and venous blood SAH groups;compared with venous blood SAH group,basilar artery wall area was reduced(40816.09±10410.51 nm2 vs 68480.89±12687.4 nm2,P<0.001),the vessel wall was thickened in arterial blood SAH group(3.07±0.59μm vs 2.36±0.25μm,P=0.007).The disordered smooth muscle cells and endothelial cells vacuolar degeneration were observed under electron microscope in arterial and venous blood SAH groups,both of which were more worse in arterial blood SAH group than in venous blood SAH group.Conclusions The DCV after SAH induced by different concentrations of oxyhemoglobin can be simulated by injecting autogenous arterial and venous blood.Reducing the concentration of oxyhemoglobin can attenuate DCV after SAH.