Prevalence of increased intracellular signal transduction in immortalized lymphoblasts from patients with essential hypertension and normotensive subjects

Objective. To determine the prevalance of enhanced signal transduction in immortalized B lymphoblasts from normotensive subjects and patients with essential hypertension. Methods. We established Epstein-Barr virus-immortalized lymphoblast cell lines from 26 normotensive and 37 hypertensive subjects. Subsequently, we quantified rises in the cytosolic free Ca concentration, [Ca](i), evoked by 0.1 μmol/l platelet-activating factor (PAF) in Fura-2-loaded cells. Results. PAF-induced [Ca](i) rises were independent of donor age in cells from normotensive and hypertensive subjects. Baseline values of [Ca](i) were not significantly different in the two groups. Using the mean + 2SD of the PAF-evoked rises in [TCa](i) above basal (110 nmol/l) as the upper normal value, we estimate that enhanced [Ca2+](i) rises are distinctly more prevalent in hypertensive subjects (27%) than they are in normotensive subjects (4%). Similarly, upon definition of normal values by the 99% confidence interval (75 nmol/l), 19% of cells from normotensive versus 43% from hypertensive subjects display enhanced intracellular signaling. Conclusion. Enhanced intracellular signal transduction could be the primary defect in approximately one-third of the overall population with essential hypertension.