[Technique of rat cochlea slicing and study of rat spiral ganglion neurons by infrared visual slice patch clamp method].
OBJECTIVE
To establishing the cochlea slice technique and infrared visual slice patch clamp method in order to observe the electrophysiological characteristics of rat spiral ganglion neurons (SGN) METHODS: SD rats were divided into three groups according to postnatal days old (0-2 d, 3-6 d and 7-14 d). Making slice of SD rat cochlear quickly, using infrared differential interference contrast (IR-DIC) technique, together with slice patch clamp, the electrophysiological characteristics of rat spiral ganglion neurons were observed, and factors which affected the quality of cochlear slice and recording of patch clamp were analyzed.


RESULTS
The success rate of 3-6 days SD was the highest, and 2-4 pieces of slice could be made from each cochlea. Cochlea connecting with partial skull and integrity of cochlear hull were the key for making slice, and the angle of modiolus axis should be adjusted to be parallel to the knife and the preparing time should be shorter. The SGN cell of good condition could be easily found and the seal test became easier with the help of infrared visual slice patch clamp method. The rest membrane potential was (-45.6 +/- 5.3) mV (x +/- s, n=52) and the current of Na+ and K+ could be activated.


CONCLUSIONS
Cochlear slice technique can retain structural integrity, cell viability and their association in cochlea, which suggest that this technique provides carrier for electrophysiological study of rat spiral ganglion neurons, and patch clamp with infrared videomicroscopy method can be used to make direct real-time observation in electrophysiological experiments of SGN, which can provide important technique support and reference for deep study of electrophysiological characteristics of SGN and auditory neurotransmission in cochlea.
Zha
Ding-jun
DJ
Department of Otorhinolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University of Chinese People's Liberation Army, Xi'an 710032, China.
Lin
Ying
Y
Qiao
Li
L
Wang
Zhi-ming
ZM
Liu
Tao
T
Li
Yun-qing
YQ
Qiu
Jian-hua
JH
D000818:Animals; D003051:Cochlea / Q000502:physiology*; D008867:Microtomy; D009474:Neurons / Q000502:physiology*; D018408:Patch-Clamp Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley; D013136:Spiral Ganglion / Q000502:physiology*