Prevalence of increased intracellular signal transduction in immortalized lymphoblasts from patients with essential hypertension and normotensive subjects.
OBJECTIVE
To determine the prevalence 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 Ca2+ concentration, [Ca2+]i, evoked by 0.1 micromol/l platelet-activating factor (PAF) in Fura-2-loaded cells.


RESULTS
PAF-induced [Ca2+]i rises were independent of donor age in cells from normotensive and hypertensive subjects. Baseline values of [Ca2+]i were not significantly different in the two groups. Using the mean + 2SD of the PAF-evoked rises in [Ca2+]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.


CONCLUSIONS
Enhanced intracellular signal transduction could be the primary defect in approximately one-third of the overall population with essential hypertension.
Gruska
S
S
Zentrum fur Innere Medizin, Klinik fur Innere Medizin A, Ernst-Moritz-Arndt-Universitat, Greifswald, Germany.
Ihrke
R
R
Stolper
S
S
Kraatz
G
G
Siffert
W
W
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002118:Calcium / Q000378:metabolism; D002461:Cell Line, Transformed; D003600:Cytosol / Q000378:metabolism; D005260:Female; D019204:GTP-Binding Proteins / Q000378:metabolism; D004854:Herpesvirus 4, Human; D006801:Humans; D006973:Hypertension / Q000378:metabolism*; D008214:Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010972:Platelet Activating Factor / Q000494:pharmacology; D015398:Signal Transduction; D017923:Sodium-Hydrogen Exchangers / Q000378:metabolism
D010972:Platelet Activating Factor; D017923:Sodium-Hydrogen Exchangers; C069139:growth factor-activatable Na-H exchanger NHE-1; D019204:GTP-Binding Proteins; D002118:Calcium