Effect of propofol on learning and memory function in neonatal rats under hypoxic conditions / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effect of propofol on the learning and memory function in neonatal rats under hypoxic conditions. Methods Eighty-four 7-day-old SD rats were randomly divided into 6 groups (n = 14 each) propofol + 18% oxygen (propofol-hypoxia, group PH), propofol + air (group PA), propofol +100% oxygen (propofol-oxygen, group PO), 0.9% normal saline (NS) + 18% oxygen (group CH), NS + air (group CA), NS + 100% oxygen (group CO). The rats received injection of intraperitoneal propofol 50 mg/kg or NS 5.0 ml/kg once a day for 7 consecutive days and they were exposed to 18% oxygen, air or 100% oxygen at the end of each injection. SaO2 and respiratory rate (RR) were monitored and recorded after administration. The rats were returned to the cage after recovery of the righting reflex. Six rats in each group were sacrificed 24 h after the 7th injection, and the brain tissues were taken to observe the apoptosis in hippocampal neurons. Morris water maze test was used to test the learning and memory function 2 weeks after administration in the other rats. Results RR was significantly lower and the escape latency at T1.2 longer in group PO than in group CO (P ＜ 0.05). RR and SaO2 were significantly decreased, apoptotic index was increased, the escape latency was prolonged and the frequency of crossing the original platform was reduced in group PA compared with group CA, and in group PH compared with group CH (P ＜ 0.05). Compared with group PO, SaO2 was significantly decreased, apoptotic index was increased, the escape latency was prolonged and the frequency of crosing the original platform was reduced in group PA (P ＜ 0.05). Conclusion Propofol induces apoptosis in hippocampal neurons and decreases the learning and memory function in neonatal rats under hypoxic conditions.