Specific RNA collection from the rat endolymphatic sac by laser-capture microdissection (LCM): LCM of a very small organ surrounded by bony tissues.

Laser-capture microdissection (LCM) is an excellent tool to selectively obtain target tissue or cells. The endolymphatic sac (ES) is part of the inner ear, and a large part of the ES is located in the temporal bone. The rat ES is conventionally harvested using stereomicroscopy. In this method, contamination is unavoidable because of its size and location; therefore, additional checks, such as in situ hybridization, are necessary to confirm the cellular localization, and quantitative analysis is difficult in the ES. We have shown a selective epithelial tissue method using LCM to obtain RNA without contamination from ES epithelial tissue.