Article: PDF OnlyFritschka Emanuel; Kribben, Andreas; Distler, Armin; Philipp, ThomasJournal of Cardiovascular Pharmacology: 1987 - p S85-S89 Free Abstract Summary Since platelet aggregation is associated with an increase in intracellular calcium concentration, the effects of the calcium entry blocker nitrendipine on 45Ca2+ influx and on aggregation of human platelets were studied. The thrombin-induced 45Ca2+ influx (60 pmol/ 10−5 platelets, p < 0.01 vs. basal influx) was reduced by nitrendipine (4 × 10−5M) to 20 pmol/108 platelets. Oral intake of 2 × 20mg/day of nitrendipine by normotensive volunteers (n = 12) reduced ADP (1.0 μM)-induced platelet aggregation. ex vivo (p < 0.05). Adrenaline-induced aggregation was inhibited (p < 0.05) at low concentrations of adrenaline (0.1 μM) at rest and also at higher concentrations (1 μM) after 5 min of exercice (150 W), while exercise itself had no measurable effect on platelet aggregation. The results demonstrate that nitrendipine, by inhibiting 45Ca2+ influx and aggregation of human platelets, potentially exerts additional warranted effects apart from blood pressure reduction. © Lippincott-Raven Publishers.