Hypertensive patients show greater platelet activation than do normotensive individuals. Platelet activation is characterized by increased phosphatidylserine (PS) exposure in the external hemilayer of the membrane, a larger number of platelet microparticles (PMP), and changes in intraplatelet-free calcium kinetics. This study evaluated whether eprosartan can protect against undesirable platelet activation. A total of 30 hypertensive patients (systolic blood pressure [SBP] 140 to 189 mm Hg; diastolic blood pressure [DBP] 90 to 109 mm Hg) without renal, liver, or cardiac organic lesions and with a mean age of 47.6 ± 9.4 years and mean body mass index (BMI) of 27.9 ± 3.9 kg/m 2 received eprosartan (600 mg/day). They were compared with 31 normotensive individuals with a mean age of 43.3 ± 6.7 years and a mean BMI of 26.8 ± 3.9 kg/m 2. Blood pressure measurements and platelet function changes were assessed at baseline (control and hypertensive patients) and after 1 and 2 months of eprosartan monotherapy (hypertensive patients only). Significant baseline to endpoint (month 2) changes in SBP and DBP were noted in the eprosartan group (SBP: baseline 152.2 ± 16.8 mm Hg, endpoint 142.2 ± 16.9 mm Hg, P < .01; DBP: baseline 93.5 ± 9.9 mm Hg, endpoint 85.8 ± 11.9 mm Hg, P < .001). Native circulating activated platelets increased in both groups after shear stress or Ca 2+ ionophore activation, and were reduced by eprosartan (after shear exposure from 104% at month 1 to 76% after 2 months of therapy). Eprosartan therapy normalized the number of microparticles after blood shear exposure (P < .01) and after exposure to Ca 2+ ionophore activation (P < .05) and significantly reduced the trend for platelets to be more readily activated in hypertensive compared with normotensive subjects (baseline to endpoint change P < .001; increase/shear versus baseline P < .001). Eprosartan partially normalizes cytoplasmic-free calcium mobilization in platelets. Eprosartan significantly reduces blood pressure and normalizes undesirable changes in platelet function. © 2004 American Journal of Hypertension, Ltd.
Labiós, M., Mart’nez, M., Gabriel, F., Guiral, V., Muñoz, A., & Aznar, J. (2004). Effect of eprosartan on cytoplasmic free calcium mobilization, platelet activation, and microparticle formation in hypertension. American Journal of Hypertension, 17(9), 757–763. https://doi.org/10.1016/j.amjhyper.2004.05.010