Expression of nicotinic acetylcholine receptor subunit α9 in type Ⅱ vestibular hair cells of rats

Aim： To explore the cell specific existence of α9 AChR in the vestibular type Ⅱ hair cells （VHC Ⅱ） of rats. Methods： To detect the expression of α9 AChR messenger RNA （mRNA） in the vestibular endorgans and single VHC Ⅱ of rats by using the reverse transcription polymerase chain reaction （RT-PCR） technique and the single cell RT-PCR technique, respectively. Results： It was shown that α9 AChR mRNA was detected in the vestibular endorgans. By using single-cell RT-PCR, mRNA encoding α9 AChR was also detected in the VHC Ⅱ of the rats. Sequence analysis of the PCR products confirmed identity to corresponding cDNA sequence in the predicted region. Condusion： We established a method which could effectively detect the cell specific expression of mRNA in an individual VHC. Present data confirm that α9 AChR mRNA is expressed in the VHC Ⅱ of rats and indicates that α9 AChR may function as a mediator of efferent cholinergic signaling in mammalian VHC.