动物低氧实验箱自动控制系统的组建及其在缺氧缺血脑损伤动物模型制作中的应用

Formation of Automatic Control System of Animal Low Oxygen Experiment Box and the Application in Establishment of Hypoxia Ischemic Brain Damages Animal Model

目的组配低氧实验箱测氧装置的自动反馈调节系统,构建完整恒稳的氧浓度自动调节机制,并利用其进行缺氧缺血脑损伤(HIBD)大鼠模型的制作。方法购买电子控氧仪,自制气体密闭箱,自主选配组合气体控制阀门和自动感应开关。连接高压氮气,使氮气经电磁控制阀门进入密闭箱;控氧仪测得的密闭箱内的氧浓度信号被输出传至电磁感应开关,后者根据设定的氧浓度阈值控制电磁阀门的通断,进而控制氮气的通入或停止,达到维持密闭箱内的氧浓度恒稳状态。利用该自动控制系统,处理7 d龄颈总动脉结扎术后新生大鼠,设定并调节密闭箱氧浓度为(8.4±0.4)%,持续2.5 h。动物处理后于不同时间点取脑组织,记录表观损伤程度后取材保存,然后利用Western blot及免疫组化方法检测处理后脑组织内分子表达。结果该系统可以稳定调控密闭箱内的氧浓度于设定范围内。颈总动脉结扎术后7 d龄大鼠,于缺氧箱中处理2.5 h后,存活率达80%～90%。动物脑组织及细胞内分子表达发生明显改变,效果明显。结论该低氧试验箱的氧浓度自动控制系统达到了较好程度的稳定性,适于进行缺氧缺血脑损伤动物模型的制作实验。

Objective To establish an automatic feedback regulation system for the oxygen detection device of low oxygen experiment box, develop a complete steady oxygen concentration automatic adjustment mechanism, and use them for the rat model of hypoxic-ischemic brain damage （HIBD）. Methods The electronic control oxygen meter was purchased and the gas sealed box was homemade, and the gas control valve and automatic induction switch were selected and combined autonomously. A high-pressure nitrogen was connected to let the nitrogen flow into the sealed box through the electromagnetic control valve. The oxygen concentration signal measured by the electronic control oxygen meter in closed box was output and transmitted to the electromagnetic induction switch which would control the on and off of the electromag- netic valve according to the set threshold of oxygen concentration ~ as to control the nitrogen gas to flux into or stop to maintain the oxygen concentration steady in the sealed box. This described automatic control system was used to process 7-day-old newborn rats with common carotid artery ligation,the oxygen concentration in the sealed box was set and adjusted to 8.4%-0.4% for 2.5 hours. The rats brain tissue was taken at different time points after processing,and the apparent damage degree was recorded then the tissues were stored, and then the molecular expression change of the processed brain tissue was detected by Western blot and immunohist hemistry. Results The system could control the oxygen concentration stability in the sealed box within the range of setting value. 7 d aged rats with common carotid artery ligation, processed for 2.5 h in the anaerobic box, had a survival rate of 80%-90%. The rat brain tissue and the intracellular molecular expression changed dramatically, the effect was obvious. Conclusion The oxygen concentration automatic control system of low oxygen test chamber achieved a good degree of stability in control, suitable for the experiments of making animal model of hypoxia ischemia brain dam- ages.