目的观察选择性头部亚低温治疗新生儿缺氧缺血性脑病(HIE)中水平基质金属蛋白酶-9(MMP-9)及行为神经评分(NBNA)的变化。方法 50例中重度HIE患儿,随机分为常规治疗组和亚低温治疗组,各25例,分别在入院时和入院后3、14 d采集静脉血,收集血清应用ELISA法检测MMP-9的水平;同时比较两组患儿同时间点的NBNA评分。结果入院时两组MMP-9比较及NBNA评分比较差异无统计学意义(P>0.05);3 d后常规组MMP-9继续升高而亚低温组无明显变化,亚低温组NBNA无明显变化而常规组继续降低;14 d后两组MMP-9均下降,但亚低温组明显低于常规组,两组NBNA评分均增加,而亚低温组明显高于常规组;血清MMP-9水平与NBNA评分呈显著负相关(r1=-0.825,r2=-0.846,r3=-0.857,P<0.05)。结论选择性头部亚低温治疗可通过抑制MMP-9的水平而有效降低缺氧缺血后脑损伤的程度,进而改善患儿行为神经能力。 Objective To observe the changes of the levels of matrix metalloproteinase-9 (MMP-9) and behavioral neurological score (NBNA) in neonates with hypoxic ischemic encephalopathy (HIE) by selective head mild hypothermia. Methods Fifty children with moderate and severe HIE were randomly divided into routine treatment group and mild hypothermia treatment group, with 25 cases in each group. Venous blood was collected at admission and 3 and 14 days after admission respectively. Serum samples were collected for the detection of MMP-9 Level; at the same time comparing the two groups of children at the same time point NBNA score. Results There was no significant difference in MMP-9 and NBNA score between the two groups on admission (P> 0.05). After 3 days, MMP-9 in normal group continued to increase while there was no significant change in mild hypothermia group and NBNA in mild hypothermia group The levels of MMP-9 decreased in both groups after 14 days, but the levels in the mild hypothermia group were significantly lower than those in the conventional group. The NBNA scores were increased in both groups, while those in the mild hypothermia group were significantly higher than those in the conventional group NBNA score was significantly negatively correlated (r1 = -0.825, r2 = -0.846, r3 = -0.857, P <0.05). Conclusion Selective head mild hypothermia treatment can effectively reduce the degree of brain injury after hypoxia-ischemia by inhibiting the level of MMP-9, thereby improving the behavioral neurological ability of children.