论文部分内容阅读
目的探讨黄芩茎叶总黄酮(SSTF)对脑缺血再灌注海马区微血管、血脑屏障(BBB)损伤的预防性保护作用。方法 SD大鼠90只,随机分为假手术组(sham组)、模型组(IR组)和SSTF预处理组,造模前1周SSTF各组灌胃给药,低、中、高剂量组分别给50、100、200 mg/(kg·d),共7d。IR组和SSTF各组制作脑缺血再灌注模型,术后评价神经功能缺损变化,干湿重法和伊文思蓝法检测脑组织含水量和微血管通透性,单宁酸-氯化铁媒染(TAFe)法显示并观测大鼠微血管密度(MVD)和微血管面积比(MVA),Real-time PCR法检测水通道蛋白4(AQP4)mRNA的表达水平,电镜观察血脑屏障完整性。结果 SSTF各组与IR组比,神经功能缺损评分、脑组织含水量、微血管通透性明显降低(P<0.01,P<0.05),MVD、MVA增加(P<0.01),AQP4 mRNA表达增强(P<0.01),BBB损伤不同程度减轻,内皮细胞肿胀渐消退,紧密连接松解好转,基膜渐连续、清晰,胶质细胞足板胞质溶解减轻,渐接近正常;SSTF中、高组上述表现较SSTF低组好转的更明显(P<0.01),SSTF中组与SSTF高组比较差异无统计学意义(P>0.05)。结论 SSTF干预对海马区微血管、血脑屏障和神经损伤有预防性保护作用,其作用机制可能是通过增加有效微血管再通数量,维持血脑屏障完整和功能,减轻脑水肿实现的。SSTF的有效预防剂量为100mg/(kg·d)。
Objective To investigate the preventive effects of total flavonoids from stems and leaves of Scutellaria baicalensis Skeletalis (SSTF) on the microvascular and blood-brain barrier (BBB) injury in hippocampus after cerebral ischemia reperfusion. Methods Ninety Sprague Dawley rats were randomly divided into sham group, model group (IR group) and SSTF pretreatment group. One week before model establishment, each group of SSTF was given intragastric administration of low, medium, high dose 50,100,200 mg / (kg · d) respectively for 7 days. IR group and SSTF group were made cerebral ischemia-reperfusion model, postoperative evaluation of neurological deficit changes, wet and dry weight method and Evans blue method to measure brain water content and capillary permeability, tannic acid - ferric chloride mordant (MVD) and microvessel area ratio (MVA) of rats were observed by TAFe method. The expression of aquaporin 4 (AQP4) mRNA was detected by Real-time PCR and the integrity of the blood-brain barrier was observed by electron microscope. Results Compared with the IR group, the scores of neurological deficit, water content in brain tissue and microvascular permeability of SSTF groups were significantly decreased (P <0.01, P <0.05), MVD and MVA increased (P <0.01), AQP4 mRNA expression increased P <0.01), BBB lesion lessened to varying degrees, endothelial cell swelling subsided, the tight junction release improved, the basement membrane gradually became clear and clear, glial cytosol lysis reduced, approaching normal; SSTF, high group above (P <0.01). There was no significant difference between SSTF group and SSTF high group (P> 0.05). Conclusion SSTF may have protective effects on the microvascular, blood-brain barrier and nerve injury in hippocampus. The mechanism may be through increasing the number of effective microvascular recanalization, maintaining the integrity and function of the blood-brain barrier and reducing cerebral edema. The effective prophylaxis dose of SSTF is 100mg / (kg · d).