[Animal modeling]-Distribution of different doses of propofol in different brain regions of newborn rats

  Objective: To explore the ideal dose of propofol for intraperitoneal anesthesia in neonatal rats and the distribution of propofol in different brain regions of neonatal rats.

  Method: Part 1: Divide the newborn rats into 5 groups randomly, inject different doses of propofol into the abdominal cavity, respectively record the anesthesia status, maintenance time, and arterial blood gas, and compare the ideal propofol dose for the newborn rats to be anesthetized in the abdominal cavity . Part 2: The newborn rats were randomly divided into anesthesia group (group A) and sedation group (group S). According to the experimental results of the first part, sedation and anesthesia doses of propofol were injected intraperitoneally, and the head was decapitated when the depth of anesthesia was appropriate. The rats were sacrificed, and the concentration of propofol in different brain regions of the rats was determined by high performance liquid chromatography.

  Results: 25 mg/kg propofol intraperitoneal injection can achieve sedation in newborn rats, while 75 mg/kg can achieve a satisfactory state of anesthesia for surgery without causing internal environment abnormalities. In the S group, the concentration of propofol in the thalamus was significantly higher than that in other brain regions (P<0.05), and there was no significant difference among other parts. The concentration of propofol in the frontal and parietal cortex of group A was significantly lower than that in other brain regions. The concentration of propofol in the hippocampus and cingulate gyrus was significantly higher than that in other brain regions (P<0.05), and there was no significant difference in other brain regions.

  Conclusion: Intraperitoneal injection of propofol is a suitable anesthesia method for newborn rats, and when the dose of propofol is different, its distribution in different brain regions is different.