The effects of repeated propofol anesthesia on spatial memory and long-term potentiation in infant rats under hypoxic conditions

摘要

Propofol is widely used as an intravenous drug for induction and maintenance in general anesthesia. Hypoxemia is a common complication during perianesthesia. We want to know the effect of propofol on spatial memory and LTP (Long-term potentiation) under hypoxic conditions. In this study, 84 seven-day-old Sprague–Dawley rats were randomly assigned into six groups (n?=?14)-four control groups: lipid emulsion solvent?+?50% oxygen (CO), lipid emulsion solvent?+?room air (CA), lipid emulsion solvent?+?18% oxygen (CH), and propofol?+?50% oxygen (propofol–oxygen, PO); and two experiment groups: propofol?+?room air (propofol–air, PA), and propofol?+?18% oxygen (propofol–hypoxia, PH). After receiving propofol (50?mg/kg) or the same volume of intralipid intraperitoneal (5.0?ml/kg), injected once per day for seven consecutive days, the rats were exposed to 18% oxygen, 50% oxygen and air, until recovery of the righting reflex. We found that the apoptotic index and activated caspase-3 increased in the PH group (P??0.05) compared with the PA group, fEPSP (field excitatory postsynaptic) potential and success induction rate of LTP reduced in all propofol groups (P??0.05). Compared with the PO group, the fEPSP and success induction rate of LTP reduced significantly in the PA and PH groups (P??0.05). Moreover, compared with CH group, the average time of escape latency was longer, and the number of platform location crossings was significantly reduced in the PH group (P??0.05). Thus, we believe that adequate oxygen is very important during propofol anesthesia.