Connexins within the rat larynx.

ABSTRACT

OBJECTIVES/HYPOTHESIS: To determine the types and localization of connexins within the rat larynx. STUDY DESIGN: Quantitative real time polymerase chain reaction (qRT-PCR) of the epiglottis and laryngeal mucosa was used to identify connexins (Cx). Immunohistochemical labeling was then used to localize the Cxs within the larynx. METHODS: Twelve larynges from 3 to 4 month old Fisher-344 rats were used. RNA was extracted (N = 8) and cDNA produced. Primers for Cx26, Cx30, Cx32, Cx37, Cx40, and Cx43 were added and qRT-PCR performed. Others larynges were serially sectioned for immunohistochemistry. RESULTS: qRT-PCR revealed Cx43, Cx32, and Cx30 within the epiglottis and Cx43 in the vocal folds and Cx43 and Cx32 within the subglottic mucosa. Immunohistochemical staining confirmed these results. CONCLUSION: The rat epiglottis is rich in Cx43, Cx32, and Cx30 whereas the vocal folds contain Cx43 and the subglottic mucosa Cx43 and Cx32. Their localizations suggest involvement in secretion for protective purposes and they may play a key role in laryngeal pathoses.