CELL-SPECIFIC EXPRESSION OF MESSENGER-RNAS ENCODING NA+,K+-ATPASE ALPHA-SUBUNIT AND BETA-SUBUNIT ISOFORMS WITHIN THE RAT CENTRAL-NERVOUS-SYSTEM

We have used in situ hybridization histochemistry to analyze the subcellular distribution of mRNAs encoding Na, K-ATPase alpha- and beta-subunit isoforms in the rat central nervous system. Substantial differences in the cell-specific pattern of expression were found for the genes encoding three isoforms of the alpha-subunit. Transcripts of alpha-1-subunit gene were detected in virtually all cell types and structures examined. Expression of alpha-2-subunit mRNA was characteristic of glia, whereas alpha-3-subunit transcripts were predominant in neurons. Transcripts encoding the beta-1 subunit were detected in neurons, whereas beta-2-subunit mRNA expression was characteristic of glia. mRNA encoding both beta-subunit isoforms was present in choroidal epithelial cells. The distribution pattern of alpha- and beta-subunit mRNAs in structures throughout the central nervous system is consistent with the possibility of six structurally distinct Na+, K+-ATPase isoenzymes.