Effect of propofol on ketamine-induced cerebral injury in neonatal rats / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effect of propofol on the cerebral injury induced by ketamine in neonatal rats. Methods Eighty 7-day-old SD rats of both sexes, weighing 12-20 g, were randomly divided into 4 groups (n = 20 each) normal saline (NS) group, ketamine-induced cerebral injury group (group K), propofol group (group P) and propofol combined with ketamine group (group PK). Group NS received intraperitoneal NS 1 ml. In groups K, P and PK, ketamine 70 mg/kg, propofol 70 mg/kg and propofol 70 mg/kg + ketamine 70 mg/kg were injected intraperitoneally once every 2 h for 3 times respectively. Ten rats in each group were selected and sacrificed at 24 h after emergence from anesthesia and the hippocampi obtained to determine the neuronal apoptosis (by TUNEL) and Bcl-2 and Bax protein expression(by immunohitochemistry). The apoptosis rate was calculated.The other 10 rats in each group were selected at 21 days after the intraperitoneal injection and the learning and memory functions (escape latency and frequency of crossing the original platform) were evaluated using Morris water maze. Results Compared with group NS, the apoptosis rate was significantly increased in group K, Bcl-2 protein expression was up-regulated in groups P and PK, and Bax protein expression was up-regulated, the escape latency was significantly prolonged and the frequency of crossing the original platform was significantly decreased in the other groups (P ＜ 0.05 .or 0.01 ). Compared with group K, the apoptosis rate was significantly decreased in group PK, Bax protein expression was down-regulated in group P, and Bcl-2 protein expression was up-regulated,the escape latency was significantly shortened and the frequency of crossing the original platform was significantlyincreased in groups P and PK ( P ＜ 0.05). Conclusion Propofol can reduce the cerebral injury induced by ketamine in neonatal rats, and the regulation of the Bcl-2 and Bax protein expression and inhibition of the neuronal apoptosis in hippocampus may be involved in the mechanism.