P-126 - Anxiety Reducing Effect of Oxytocin on Basolateral Amgydala by Using Electrophysiological Method

Abstract

Objective

The amygdala whis is part of limbic system is activated in case of fear and anxiety. This study evaluated the effects of oxytocin on the basolateral amygdala(BLA) in spontaneous EEG.

Materials and methods

In this study 7 Sprague-Dawley adult male rats were used.Under anesthesia with the help of drill by opening a small hole,then by taking bregma as reference with the stereotaxic method(Anteroposterior:−2.8 mm, Lateral:+4.8 mm,Ventrodorsal:−8.5 mm), bipolar EEG electrode was placed to the BLA.Electrodes were fixed by using a dental restorations material.

Electrodes placed 3 days later, the animals are awake in their cages, spontaneous EEG recordings taken from the amygdala. Then, rats (n = 7) 0.9% isotonic NaCl intraperitoneally applied, the EEG was recorded amygdala their cages.

1 day later to the same rats(n = 7) oxytocin 10 IU/Kg were applied IP,5 minutes later of injection of oxytocin EEG records were taken in their own cage.

System records were taken 20 minutes by Biopac MP30 amplifier system in the range of 1–60 Hz band,with 10.000 amplification. We affirmed electrode location histologically following euthanisation.

Results

There is significant(p < 0.05) diminution in delta frequency (&64.4 ± 10.9) of rats which is administred isotonic than spontan EEG records (%79.5 ± 12.8).

There is significant(p< 0.05) increasement in delta frequency (76.8±12.5)of rats which is administred oxytocin than isotonic injected rats (%64.4±10.9).

Conclusion

Anxiety caused by injection of isotonic,is augmented EEG frequency if we compare with resting EEG records.Oxytocin,diminue the EEG frequency of rats which has injection anxiety.This results show electrophyiologicly that oxytocin is an powerfull anxiolytic.