脑缺血大鼠脾质量指数与神经功能缺损评分及脑梗死体积的相关性

Correction of spleen mass index with neurological dysfunction scores and infarct volume in brain ischemia rats

目的脾在缺血后继发性脑损伤的发病机制中占有重要位置。文中旨在探讨永久性脑缺血大鼠模型脾质量指数与神经功能缺损评分及脑梗死体积的变化规律及其相关性。方法 30只雄性SD大鼠随机分为假手术组、缺血3 d组和缺血7 d组,每组10只。缺血3 d组和缺血7 d组采用线栓法建立右侧永久性大脑中动脉闭塞模型,于术后清醒时和缺血3、7 d分别采用Longa评分法行神经功能缺损评分;于缺血3、7 d称取脾质量、计算脾质量指数,TTC染色法测量脑梗死体积,HE染色观察脑组织病理形态学改变。结果与缺血7 d组比较,缺血3 d组脾质量指数下降[(1.62±0.58)mg/g vs(0.87±0.59)mg/g]、神经功能缺损评分提高[1.00(1.00,1.25)vs 2.00(1.75,2.25)]、脑梗死体积增大[(18.67±7.92)%vs(36.20±14.92)%](P<0.05)。与假手术组脾质量指数[(1.90±0.22)mg/g]相比,缺血3 d组显著下降(P<0.01)。HE染色证实,缺血3 d组较缺血7 d组大脑皮质病理损伤明显。相关性分析显示,脾质量指数与神经功能缺损评分、脑梗死体积百分比呈负相关(r=-0.851,P=0.019;r=-0.717,P=0.013)。结论在永久性脑缺血大鼠模型中,通过监测外周脾体积的变化,对预防和改善缺血后脑损伤具有重要意义。

Objective The spleen plays an important role in brain ischemia-induced cerebral injury. This study aimed to explore the correlation of the spleen mass index with the neurological function scores and infarction volume following permanent occlusion of the middle cerebral artery （pMCAO） in rats. Methods Thirty male SD rats were equally randomized into a sham operation, a 3- day brain ischemia, and a 7-day brain ischemia group, The pMCAO model was established by ligation in the right brain of the rats. Neurological function scores were obtained with the Longa 5-Point Scale at 0, 3, and 7 days after modeling, and at 3 and 7 days, the spleen mass index was calculated, the infarction volume measured by TTC, and brain histopathological changes evaluated by HE staining. Results Compared with the 7-day ischemia group, the 3-day ischemia rats showed significantly reduced spleen mass index （ [ 1.62 ± 0.58 ] vs [ 0.87 ± 0.59 ] mg/g） and increased neurological function score （ 1.00 [ 1.00, 1.25 ] vs 2.00 [ 1.75, 2.25 ] ） and infarct volume （ [ 18.67 ± 7.92 ] vs [ 36.20 ± 14.92 ] % ） （ all P 〈 0.05 ）. An extremely significant decrease was found in the spleen mass index of the 3-day ischemia rats in comparison with that of the animals in the sham operation group （ [ 1.90 ± 0.22 ] mg/g） （P 〈0.01 ）. HE staining revealed more obvious pathological injury of the cerebral cortex in the 3-day than in the 7-day group. The spleen mass index was negatively correlated with the neurological dysfunction score （r = -0.851, P =0. 019） and infarction volume （r = -0. 717, P = 0. 013）. Conclusion In pMCAO rats, measurement of the spleen mass index contributes significantly to the prevention and improvement of ischemia-induced cerebral injury.