Sustained-release nifedipine (nifedipine-L) suppresses plasma thromboxane B2 and 6-keto prostaglandin F1 alpha in both young male smokers and nonsmokers.
Sustained-release nifedipine (nifedipine-L) (40 mg twice a day) was administered orally to healthy young adult male smokers and nonsmokers for 10 days, and its effects on platelet aggregation, beta-thromboglobulin and platelet factor 4 levels, and plasma thromboxane B2 (TxB2) and 6-ketoprostaglandin F1 alpha (6-Keto-PGF1 alpha) concentrations were studied. The plasma nifedipine-L concentration in smokers (46.0 +/- 7.4 ng/ml) was significantly lower than that in nonsmokers (88.2 +/- 1.2 ng/ml). Nifedipine-L did not affect platelet aggregation induced by adenosine diphosphate, collagen, or epinephrine in either smokers or nonsmokers. The plasma beta-thromboglobulin level on the tenth day of nifedipine-L administration in nonsmokers was lower than that in smokers, but there were no significant differences either with or without nifedipine-L or between nonsmokers and smokers. Nifedipine-L had no effect on the concentration of platelet factor 4 in either smokers or nonsmokers. On the other hand, nifedipine-L significantly decreased the plasma TxB2 and 6-keto-PGF1 alpha concentrations in both smokers and nonsmokers. Thus we concluded that nifedipine-L suppressed the production of plasma TxB2 from platelets and also subsequently suppressed the production of 6-keto-PGF1 alpha and that this action was not affected by cigarette smoking.
Nakashima
Y
Y
Second Department of Internal Medicine, University of Occupational and Environmental Health Japan, School of Medicine.
Kawashima
T
T
Nandate
H
H
Yashiro
A
A
Kuroiwa
A
A
D015121:6-Ketoprostaglandin F1 alpha / Q000097:blood*; D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D003692:Delayed-Action Preparations; D003971:Diastole; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D009543:Nifedipine / Q000008:administration & dosage* / Q000494:pharmacology; D012907:Smoking; D013929:Thromboxane B2 / Q000097:blood*; D014280:Triglycerides / Q000097:blood
D003692:Delayed-Action Preparations; D014280:Triglycerides; D013929:Thromboxane B2; D015121:6-Ketoprostaglandin F1 alpha; D009543:Nifedipine