缺氧缺血性脑损伤新生大鼠脑干听觉诱发电位的动态变化

Development of brainstem auditory evoked potentials in rat pups with hypoxic-ischemic brain injury

目的：探讨缺氧缺血性脑损伤新生大鼠脑干听觉诱发电位（BAEP）的动态变化。方法：30只出生13天的新生SD大鼠随机分为对照组和缺氧缺血组，每组15只。将出生后第13天新生大鼠结扎左侧颈总动脉后，置于含氧8％的低氧环境中3h建立缺氧缺血性脑损伤动物模型。出生后第14、20、27、37、47、57、67和77天检测大鼠的BAEP。结果：缺氧缺血组新生大鼠3h缺氧复氧1h后，表现为向左侧旋转，爬行时右侧后肢呈现拖步。出生后第14～47天缺氧缺血组大鼠BAEP波峰潜伏期（PL）和波峰间潜伏期（IPL）较对照组显著延长（P〈0．05或P〈0．01），这些鼠的BAEP的PL及IPL均随年龄的增加而缩短，并且鼠可发育成熟。结论：缺氧缺血性脑损伤新生大鼠BAEP有显著的可逆性异常变化，其PL和IPL是动态监测与客观评价新生期缺氧缺血性脑损伤和听觉障碍的灵敏指标。

Objective：To probe into the development of brainstem auditory evoked potentials （BAEP） in rat pups with hypoxic - ischemic brain injury. Methods： Thirteen day-old rat pups were randomly divided into the control and hypoxic - ischemic groups, 15 rats in each group. A combination of left common carotid artery ligation and exposure to low oxygen environment （8%O2） for 3 h was used to induce hypoxicischemic brain injury. BAEP were recorded with evoked potential recorder on the postnatal days 14,20,27,37,47,57,67 and 77. Results.. The rat pups in the hypoxic-ischemic group rotated toward left side and crawled with the dragged right leg after staying in low oxygen environment for 3 h. The peak latencies （PL） and interpeak lateneies（IPL） of BAEP were much longer from the postnatal days, 14 to 47 in the hypoxic - ischemic group than in control one （P〈0.05 or P〈0.01）, and they could shorten significantly with age to mature values. Conclusion.. There are significanty reversible changes of BAEP in the rat pups with hypoxic-ischemic brain injury, and the PL and IPL of BAEP are the sensitive and objective indexes for developmentally monitoring and evaluating hypoxic-ischemic brain and auditory injury in neonatal period.