[Epithelial sodium channel subunit mRNA expression in acutely isolated rat alveolar type II cells].

OBJECTIVE: To investigate the epithelial sodium channel (ENaC) subunit mRNA expression in acutely isolated rat alveolar type II (ATII) cells. METHODS: Acutely isolated ATII cells from 20 SD rats were purified and ENaC alpha, beta, gamma-subunit mRNA levels were determined by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: mRNA expressions of all the subunits were detected in the ATII cells, and ENaC alpha-subunit mRNA showed significantly higher expression than beta- and gamma-subunit mRNAs, and the expressions of the latter two mRNAs were comparable. CONCLUSION: As the predominant ENaC subunit expressed at the mRNA level in rat ATII cells, the alpha-subunit of ENAC plays an important role in alveolar fluid clearance.