[The effect of white noise on activity of nitric oxide synthase in cochlear nuclei of guinea pigs].
This experiment adopted lipoic amido dehydrogenase (NADPH-d) histochemistry method and image pattern analysis technique to investigate the relationship between nitric oxide synthase (NOS) neurons and activity of NOS and auditory threshold, and to explore the possible role of NOS neurone in cochlear nuclei of guinea pigs after exposed to white noise. The results showed that the quantity and staining intensity of positive NOS neurons in cochlear nuclei increased obviously after exposed to noise. It reached the peak 2 weeks later and remained high expression during 3-4 weeks. It restored 5 weeks later but was still higher than normal. Within 7 days after exposed to noise, activity of NOS in cochlear nuclei deviated from ABR threshold. After 7 days, activity of NOS had a positive correlation with ABR threshold (r = 0.9571, P < 0.01). It is suggested that NOS in cochlear nuclei might play double role after exposed to white noise. On one hand, a certain range of activity of NOS might help to restore injured neurons. On the other hand, over expression of NOS might exacerbate the injury of cochlear nerves.
Jiang
H
H
Department of Otorinolaryngology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032.
Huang
W
W
Wang
J
J
D000818:Animals; D017626:Cochlear Nucleus / Q000201:enzymology*; D016057:Evoked Potentials, Auditory, Brain Stem; D005260:Female; D006168:Guinea Pigs; D008297:Male; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D052248:Nitric Oxide Synthase Type I; D009622:Noise; D011897:Random Allocation
D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I