Effects Of Transformer Noise On The Auditory Function,Behavior And Related Neurophysiological Functions In SD Rats

Objective:To determine the effects of transformer noise on the auditory function,behavior and related neurophysiological functions in SD rats.Methods:90 healthy SD rats(half male and female)with normal hearing were randomly divided into experimental group A,B and control group C.The experimental groups were exposed to the recorded transformer noise for 8 weeks(10 hours per day,10:00 pm-8:00 am).Group A was exposed to the pressure level 65 dB SPL at Max(noise spectrum:100-800 Hz),group B was exposed to the pressure level 60 dB SPL at Max(noise spectrum:100-800 Hz),and control group C were maintained under the same conditions,without noise stimulation.The indexes of behavioral changes(tail suspension test,open field behavior test),auditory functions,serum biochemical,stress state and immunologic function of SD rats were determined and compared among the three groups after an 8 weeks' noise exposure;After noise exposure,changes in glutamic acid(Glu),gamma-aminobutyric acid(GABA),dopamine(DA),and 5-hydroxytryptamine(5-HT)levels,and morphological changes in the neurons and synapses of the hippocampus were recorded and compared.Results:In the 8 weeks of transformer noise exposure,the rats showed normal physiological growth,and there was no significant difference(P>0.05)between the study and control groups.After noise exposure,indices of the behavioral experiments,auditory functions,serum biochemical,stress state and immunologic function of the groups were compared,and no statistically significant difference was observed(P>0.05).In addition,there were no significant differences in the Glu,GABA,DA,and 5-HT content and morphological changes(P>0.05).Conclusion:Our results showed that continuous exposure to transformer noise(sound pressure level 65/60 dB SPL,noise spectrum:100-800 Hz)for 8 weeks(10 hours/day)had no significant effect on the behavior,auditory functions,serum biochemical,stress state and immunologic function and related neurophysiological functions of SD rats.These results could form the basis for further studies on the impact of transformer noise.