Regulation of distal nephron K+ channels (ROMK) mRNA expression by aldosterone in rat kidney

Abstract
1 The expression of ROMK mRNA isoforms in rat kidney was measured using competitive polymerase chain reaction. Under basal conditions the expression of ROMK2 and 3 mRNA was significantly higher than that of ROMK1 or 6. 2 Administration of aldosterone for a period of 1 week significantly increased the mRNA expression not only of the α1-subunit of the Na+-K+-ATPase, but also of ROMK2, 3 and 6. 3 These data not only provide evidence that ROMK K+ channels may be involved with mineralocorticoid-sensitive K+ secretion in the distal nephron, but also demonstrate for the first time that ROMK6 may be involved in this process.