Background: Postoperative cognitive dysfunction (POCD) is known as a decline in cognitive performance that begins days after the surgery and lasts for weeks or months. POCD is usually self-limited but can be long-lasting or even permanent in elderly patients. Experimental studies have shown that cognitive dysfunction can be induced solely by anesthetics. However, the detailed mechanism underlying POCD is not well addressed yet. In this study, we investigated the effects of pentobarbital on cognitive performance.
Methods: Male 5-weeks-old ddY mice were anesthetized by an intraperitoneal injection of pentobarbital and subjected to novel object recognition (NOR) test for evaluation of memory performance.
Results: Pentobarbital induced anesthesia in a dose-dependent manner, and at 100 mg/kg, anesthesia was sustained for about 2 hours. Cognitive decline occurred in the NOR test at 3 days after anesthesia, but not in the test at 1 or 6 days after anesthesia. The cognitive dysfunction was attenuated by pre-administration of the hypoxia-inducible factor (HIF) signal inhibitor, YC-1 or acriflavine.
Conclusion: Delayed cognitive dysfunction induced by pentobarbital presumably reflect the symptoms of POCD. Present results suggest that the activation of HIF signal is involved in the development of POCD.