高血压急性脑损害大鼠模型建立的实验观察

Experimental observation on the rat model of acute hypertensive brain damage

目的:为进一步研究高血压脑损害,建立一个急性高血压脑水肿的动物模型。方法:雄性SD大鼠30只,随机分成对照组和实验组各15只。实验组经静脉输入盐酸去氧肾上腺素,待血压升至最高值后维持30min,对照组则以相同速度输入生理盐水30min。分别静注伊文氏蓝染色、普通苏木精-伊红染色光镜观察、镧醛灌注电镜观察等方法对模型进行评价。结果:伊文氏蓝染色可见:对照组大鼠除缺乏血脑屏障的部位被染成蓝色外,其他部位的脑组织均未见蓝染;实验组则大脑、小脑均有斑片状蓝染。镧醛灌注电镜观察可见:对照组镧离子局限在微血管腔内;实验组则见镧离子分布到血管外间隙和细胞间隙中。说明实验组血脑屏障有破坏。结论:静脉输注盐酸去氧肾上腺素,使血压急剧升到170mmHg(1mmHg=0.133kPa)左右并维持30min可以成功制成大鼠急性高血压脑水肿模型。

AIM:To establish an animal model of acute hypertensive brain edema for the fur ther study on brain damage induced by hypertension. METHODS:Thirty male SD rats were randomly divided into control group and exper imental group with 15 rats in each group.Hydrochloric phenylephrine was injected intravenously into the experiment rats so as to maintain blood pressure at the highest level for 30 minutes, while normal saline was injected into the control rats at the same speed for 30 minutes.To evaluate the model,methods of brain sta ining with intravenous injection of Evan's blue,microscope observation of common HE stained specimen, electronic microscope observation of lanthanum-polymerisa tum fixation fluid perfused brain were used. RESULTS:Evan's blue staining showed that no brain tissue was stained into blue except those parts lack of blood-brain barrier in the control group, whereas,b lue patches were seen in cerebrum and cerebellum of the experiment rats.Electron ic microscope observation revealed that lanthanum was confined in the cerebral m icrovessel of the control rats,whereas,lanthanum was distributed in perivascular space and intercelular space of the experiment tats.These results suggested tha t blood-brain barrier was impaired in the experiment rats. CONCLUSION:Intravenous injection of gydrochloric phenylephrine for increasing the blood pressure to 170 mm Hg(1 mm Hg=0.133 kPa) and maintaining the blood pre ssure at the highest level for 30 minutes can successfully establish a rat model of hypertensive brain edema.