Effects of diltiazem on platelet activation and cytosolic calcium during percutaneous transluminal coronary angioplasty
- VernacularTitle:PTCA围手术期硫氮酮对血小板活性和钙动力学的影响
- Author:
Hemin DAI
;
Junzhu CHEN
;
Qianmin TAO
;
Jianhua ZHU
;
Furong ZHANG
;
Liangrong ZHENG
;
Yuangang QIU
- Publication Type:Journal Article
- Keywords:
Angioplasty, transluminal, percutaneous coronary;
Blood platelets;
Diltiazem;
Calcium
- From:
Chinese Journal of Pathophysiology
2000;0(07):-
- CountryChina
- Language:Chinese
-
Abstract:
AIM: To evaluate effects of diltiazem on platelet hyperreactivity in situations associated with endothelial injury and their possible relationship to cytosolic calcium concentration. METHODS: Blood samples were collected at 7 time points from 35 patients undergoing percutaneous transluminal coronary angioplasty (PTCA) who received combined diltiazem and aspirin/ticlopidine therapy or aspirin/ticlopidine therapy alone. Platelet expression of glycoprotein Ⅱb/Ⅲa and cytosolic calcium concentration were measured, respectively, by whole blood flow cytometry and fluorospectrophotometry. The effects of diltiazem of different concentrations on expression of glycoprotein Ⅱb/Ⅲa were also studied in vitro in blood samples from patients with chronic stable angina. RESULTS: Of the two treatments, aspirin/ticlopidine therapy did not prevent an acute increase of expression of glycoprotein Ⅱb/Ⅲa 5 minutes and 10 minutes after first inflation and 10 minutes after PTCA, whereas combined diltiazem and aspirin/ticlopidine therapy had a significant inhibitory effect. In the group receiving aspirin/ticlopidine therapy, there was a short-term elevation of platelet [Ca~(2+)]i immediately following PTCA which was significantly reduced by diltiazem treatment. Expression of glycoprotein Ⅱb/Ⅲa was significantly inhibited in vitro by diltiazem in the concentration of 200 ?g/L or higher, but not 50 ?g/L. CONCLUSIONS: Combined diltiazem and aspirin/ticlopidine therapy significantly inhibited platelet activation that continued in the presence of conventional aspirin/ticlopidine treatment. Antiplatelet effects of diltiazem were probably a consequence of reduction of platelet [Ca~(2+)]i and may only be achieved in higher than therapeutic concentrations. [
