Expression of nicotinic acetylcholine receptor subunit α9 in type Ⅱ vesti-bular hair cells of rats

Aim:To explore the cell specific existence of α9 AChR in the vestibular type Ⅱ haircells(VHC Ⅱ)of rats.Methods:To detect the expression of α9 AChR messengerRNA(mRNA)in the vestibular endorgans and single VHC Ⅱ of rats by using thereverse transcription polymerase chain reaction(RT-PCR)technique and the singlecell RT-PCR technique,respectively.Results:It was shown that α9 AChR mRNAwas detected in the vestibular endorgans.By using single-cell RT-PCR,mRNAencoding α9 AChR was also detected in the VHC Ⅱ of the rats.Sequence analysisof the PCR products confirmed identity to corresponding cDNA sequence in thepredicted region.Conclusion:We established a method which could effectivelydetect the cell specific expression of mRNA in an individual VHC.Present dataconfirm that α9 AChR mRNA is expressed in the VHC Ⅱ of rats and indicates thatα9 AChR may function as a mediator of efferent cholinergic signaling in mamma-lian VHC.