Changes in the level of NHE1, ATP1B1, NKCC1, and GAPDH mRNAs in lymphocytes from patients with mild essential hypertension

To study whether lymphocytes from patients with mild essential hypertension differ from healthy persons in the levels of mRNAs encoding Na/H exchanger (NHE1), some other ion transporters, i.e. sodium pump (ATP1B1), NaK2Cl symporter (NKCC1), and proteins unrelated to ion transport: glycolytic enzyme (GAPDH), antiapoptotic regulator (BC1-2) and kinase hSGK. Methods: Human peripheral blood lymphocyte mRNAs were assayed by RT PCR procedure. The amount of cDNA was quantified by photometry of electrophoretic bands stained with ethidium bromide, using digital photocamera and PC program. Hypertensive group included 26 males aged 18-30 years with mild essential hypertension, while normotensives -18 males with the same baseline characteristics except that for blood pressure. Results: The levels of NHE1, ATP1B1, NKCC1, GAPDH mRNAs, but not Bcl-2 or hSGK, in lymphocytes from hypertensives are higher than in normotensives by about factor 2.4-2.6 for ion transporters and 3.5 for GAPDH. Conclusions: The lymphocytes from young males with mild hypertension differ from normotensive ones in that there is a change in abundance of a group of mRNAs comprising not only NHE1, but either ATP1B1, NKCC1, and GAPDH mRNAs. The NHE1 effect is not specific.

hypertension, gene expression, leukocytes, ion exchangers, Na/K pump experimental, blood, subcellular, pathophysiology

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