An Experimental Study on the Protective Effects of Ginkgo Biloba Extract on the Spiral Ganglion Neuron of the Rat Cochlea / 听力学及言语疾病杂志

ABSTRACT

Objective To investigate the protective effects of the extract of ginkgo biloba(EGb)on the spiralganglion neuron(SGNs)in cochlea tissues on the hearing loss induced by noise in rats.Methods Thirty-six healthy animals were randomly divided into three groupsthe normal control group(n=12).the noise exposured group(n =12)and the EGb treamment group(n=12).The control group received no noise and no medications.The other two groups were exposed to the noise of 110 dB SPL for consecutively 10 days,6 hours per day.The treatment group rats were injected with 10 ml/d EGb while the other two groups with 0.9%saline of the same amount.The experiment lasted for ten days.The rats were measured by auditory brainsterm response(ABR)before and after niose exposure.The ultrastructural changes of SGNs were detected by tranismision electron microscpoe(TEM) and the contents of malondiadehyde(MDA) and activities of superoxide dismutase(SOD)were also measured.Results Hearing were signifcantlly decreased in the experimental group.Nevertheless,EGb relatively reduced the contents of MDA while increased the activities of SOD.Conclusion EGb seems to be able to moderately pretect SGNs and to play a preventive and remedial role in noise-induced hearing loss.