Effect of Isoflurane Exposure with Administration of Polyunsaturated Fatty Acids on Cognition in Developing Rats

Özet

Objective: The developing brain is vulnerable to the negative effects of anaesthetics. We aimed to investigate the effect of isoflurane and polyunsaturated fatty acids (PUFAs) on cognition.Methods: A total of 64, ten days old rats were randomly divided into 4 groups: group O2 (oxygen group), group Iso (isoflurane group), groupIso-S (isoflurane+saline) and group Iso-PUFAs (isoflurane+intraperitoneal [IP] PUFAs emulsion). Rats in groups Iso, Iso-S and Iso-PUFAs wereexposed to 1.5% isoflurane in 50% oxygen for 6 hours. Rats in group O2 breathed only 50% oxygen. Before anaesthesia, rats in group Iso-Swere administered 0.5 mL isotonic and rats in group Iso-PUFAs were administered 5 mL kg-1 PUFAs emulsion by IP injection. The Morris watermaze (MWM) test was performed on postnatal 28-33 days. Histological evaluation and immune histochemical staining (Bcl-2 antibody) wereperformed on postnatal day 11 on rat brains.Results: As demonstrated by the reduction in the escape latency on days 3, 4 and 5 compared with day 1, all rats learned the task during theacquisition period. In contrast to others, rats in group Iso spent significantly lower time to find the platform on day 2 than on day 1 (p=0.034). Nosignificant difference was found among the groups in terms of time spent in finding the platform. There were no significant differences in probetrials, histological features and Bcl-2 immunoreactivity among the groups.Conclusion: Isoflurane did not cause cognitive dysfunction and neuronal death, and a single dose of PUFAs emulsion had no effect on cognition either.