脉冲磁疗对脑出血大鼠脑内谷氨酸和胰岛素样生长因子-1表达的影响

Effects of pulse magnetic therapy on expression of glutamate and insulinlike growth factor-1 after cerebral hemorrhage in rats

目的观察脉冲磁疗对脑出血大鼠脑组织中谷氨酸和胰岛素样生长因子-1(IGF-1)表达的影响。方法清洁级雄性SD大鼠36只,随机分成假手术组、模型组和磁疗组,每组又分为3 d组和7 d组,每个亚组各6只大鼠。采用立体定向技术制作脑出血模型。磁疗组于术后2 h开始脉冲磁疗干预,异名磁极对置于头部,磁距10 cm,平均磁场强度0.01 T,频率50 Hz,20 min/次,1次/d。并于脑出血3、7 d时分别对各组大鼠进行神经行为学评定、谷氨酸和IGF-1浓度的测定。结果磁疗3、7 d组改良神经功能缺失评分(m NSS)均比对应的模型组下降,差异有高度统计学意义(P<0.01)。脑出血后,脑组织中谷氨酸表达增加,经过脉冲磁疗3、7 d后,谷氨酸浓度均明显下降,低于模型组,差异有高度统计学意义(P<0.01)。正常脑组织内IGF-1有少量表达,脑出血后,其表达增加;经过磁疗3、7 d后,与模型组相比,IGF-1水平均明显升高,差异有高度统计学意义(P<0.01)。结论脉冲磁疗可以一定程度上促进脑出血大鼠神经功能的恢复,其机制可能与谷氨酸水平的下降和IGF-1的表达增加有关。

Objective To observe the effects of pulsed magnetic therapy on the expression of glutamate and insulin- like growth factor-1 （IGF-1） after cerebral hemorrhage in rats. Methods 36 male adult Sprague-Dawley rats were randomly divided into the sham group （n=12）, model group （n=12） and magnetic therapy group （n=12）. Each group was randomly divided into 3 d and 7 d subgroups, with 6 rats in each subgroup. The cerebral hemorhage model of rats was made using the technology of stereotaxis. The magnetic therapy group was treated with pulsed magnetic therapy （0.01 T, 50 Hz, 20 min/times, 1 times/d） after hemorrhage 2 h. The modified neurological severity score （mNSS）, the concentration of glutamate and IGF-1 were evaluated at 3 d and 7 d after cerebral hemorrhage. Results Compared to the model group, the mNSS scores in 3 d and 7 d magnetic therapy group decreased significantly （P 〈 0.01）. After cerebral hemor-rhage, the concentration of glutamate increased; in the magnetic therapy group, the concentration of glutamate was significantly decreased than in the model group after hemorrhage 3 d and 7 d （P 〈 0.01）. IGF-1 had little expression in the normal brain tissue, after cerebral hemorrhage, its expression increased; the concentration of IGF-1 in the magnetic therapy group was significantly increased than in the model group after hemorrhage 3 d and 7 d （P 〈 0.01）. Conclusion Pulsed magnetic therapy can promote the recovery of neural function in rats. This effect may be associated with the decline of glutamate and the higher expression of IGF-1.