奥扎格雷钠对局灶性脑缺血大鼠的神经保护作用

The neuroprotective effect of ozagrel sodium on focal cerebral ischemia in rats

目的探讨奥扎格雷钠对大脑中动脉阻塞(MCAO)大鼠的神经保护作用及其机制。方法随机将72只SD大鼠分为假手术组,单纯缺血组,尼莫地平组,奥扎格雷钠低、中、高剂量组,每组12只大鼠。以线栓法制备MCAO模型。奥扎格雷钠干预组和尼莫地平组分别在模型制备前腹腔给予7.2、14.4、28.8 mg/kg的奥扎格雷钠注射液(质量浓度为20 g/L)和2 mg/kg的尼莫地平注射液(质量浓度为0.2 g/L),1次/d,连续5 d,并于模型制备前1 h给药1次。单纯缺血组及假手术组用与奥扎格雷钠中剂量组相同体积的等渗盐水行腹腔注射,疗程与奥扎格雷钠干预组相同。术后大鼠清醒后进行神经功能缺损评分;24 h断头取脑制备组织匀浆,用放射免疫法测定内皮素1(ET-1)和降钙素基因相关肽(CGRP)的活性;光镜及透射电子显微镜下观察脑组织海马区病理学改变。结果①假手术组、单纯缺血组、尼莫地平组,及奥扎格雷钠低、中、高剂量组神经行为学评分分别为0.0±0.0、3.1±0.9、2.5±0.6、2.7±0.8、2.1±0.7、2.0±0.3。奥扎格雷钠能显著降低神经功能缺损评分(P<0.01,P<0.05)。②尼莫地平组和奥扎格雷钠低、中、高剂量组CGRP分别为(14.2±1.9)、(14.1±3.2)、(15.9±2.5)、(16.2±2.5)pg/mg(脑湿重);ET-1分别为(2.6±0.7)、(3.0±0.8)、(2.1±0.6)、(2.0±0.5)pg/mg(脑湿重),各组CGRP、ET-1与单纯缺血组的(10.6±2.8)、(3.5±0.9)pg/mg(脑湿重)比较差异均有统计学意义(P<0.05,P<0.01),奥扎格雷钠中、高剂量组与尼莫地平组比较差异亦有统计学意义(P<0.05)。③光镜及透射电镜观察均显示奥扎格雷钠可明显减轻神经细胞的损伤程度。结论奥扎格雷钠可通过调节脑缺血后脑组织中ET-1、CGRP的水平,减轻神经细胞损伤的发生。

Objective To investigate the neuroprotective effect of ozagrel sodium on the focal cerebral ischemic rats model and its mechanism. Methods Seventy-two SD Rats were randomly allocated into sham-operation, focal cerebral ischemia, nimodipine treated （10 ml/kg） and ozagrel sodium treated groups. The ozagrel sodium were used in low （0. 36 ml/kg）, moderate （0. 72 ml/kg ）, and high （ 1.44 mL/kg） doses （ n = 12 in each group） separately. The rat model was made by middle cerebral artery thread occlusion MCAO method. Before making the model, ozagrel sodium were injected in close of 7. 2, 14. 4 and 28. 8 mg/kg （ quality concentration 20 g/L） separately in the ozagrel sodium group, and nimodipine 2 mg/kg （quality concentration 20 g/L） were injected intraperitoneally once per clay for 5 days, and one close was given before making the model. The same volume of isotonic saline was injected intraperitoneally in the focal cerebral ischemia and sham-operation groups. The neurological deficits were evaluated after the rats waked up; and were killed by decapitation and their brains were taken out for detection of the activity of endothelin-1 （ET-1） and calcitonin gene related peptide （CGRP） by radioimmunoassay, the pathologic changes of CA1 hippocampal area were observed under light and transmission electron microscopes. Results The scores of neuroethology in the sham-operation, focal cerebral ischemia, nimodipine, and ozagrel sodium low-, moderate- and high-dose groups were 0. 0 ±0. 0, 3. 1 ±0. 9, 2. 5 ±0. 6, 2.7 ±0. 8, 2. 1 ± 0. 7, and 2. 0 ± 0. 3, respectively. Ozagrl sodium could significantly reduce neurological deficit scores （P 〈 0. 05, 0. 01）. The content of CGRP in the nimodipine, and low-, moderate- and high-dose ozagrel sodium groups were （ 14. 2 ± 1.9）, （ 14. 1 ± 3.2）, （ 15.9 ± 2. 5）, （ 16. 2 ± 2. 5） pg/mg wet weight, respectively; the content of ET-1 in these groups were （2. 6 ±0. 7）, （3.0 ±0. 8）, （2. 1 ±0. 6）, and （2.0 ±0. 5） pg/mg weight, respectively. There were significant differences in the content of CGRP and ET-1 in all groups as compared with the focal cerebral ischemia group [ （ 10. 6 ±2.8） and （3.5 ±0. 9） pg/mg wet weight, P 〈 0. 05, 0.01 ], and there were also significant differences between the low-, moderate- and high-dose ozagrel sodium groups and nimodipine group. Observation under light and transmission electron microscopes showed that ozagrel sodium could remarkably alleviate the nerve cell damage. Conclusion Ozagrel sodium may alleviate the nerve cell damage by modulating the levels of ET-1 and CGRP in brain tissues after cerebral is- chemia.