Platelet-vessel wall interactions with third-generation oral contraceptives: no evidence of detrimental effects.
Because of the association of oral contraceptives (OC) and cigarette smoking with an increased thrombotic risk, we evaluated thromboxane (TX) and prostacyclin urinary (u) metabolites, as in vivo indices of platelet-vessel wall interactions, in women assigned to third generation OC. Twenty-eight women (15 smokers) underwent a 6-month trial of 30 microg ethinylestradiol plus 0.150 mg desogestrel. Cotinine plasma levels were elevated only in persons classified as smokers and serum TXB2 determination confirmed the absence of cyclooxygenase inhibition throughout the study. u-TXB2 and 11-dehydro-TXB2 were higher in smokers than in non-smokers. OC decreased u-11-dehydro-TXB2 both in smokers (from (pg/micromol creatinine) 35.1+/-6.9 to 15.8+/-2.8; P<0.025) and non-smokers (from 31.7+/-9.8 to 20.6+/-4.8, P = N.S.). u-6-keto-prostaglandin(PG)F1alpha excretion, also higher in smokers compared to non-smokers, was also reduced after OC in smokers (from (pg/micromol creatinine) 24.3+/-5.2 to 14.8+/-2.3; P<0.05). Smokers also had a trend to higher u-2,3-dinor-6-keto-PGF1alpha, marginally reduced by OC. Thus, the OC regimen used here improves - if anything - platelet vessel wall interactions as assessed by prostanoid production in vivo. The prothrombotic tendency associated with the use of OC in smokers does not appear to be mediated by changes in platelet-vessel wall interactions.
Fruzzetti
F
F
Department of Obstetrics and Gynecology, the University of Pisa, Italy.
Giannessi
D
D
Ricci
C
C
Bernini
W
W
Puntoni
R
R
Genazzani
A R
AR
De Caterina
R
R
D015121:6-Ketoprostaglandin F1 alpha / Q000652:urine; D000293:Adolescent; D000328:Adult; D001792:Blood Platelets / Q000187:drug effects* / Q000502:physiology; D001808:Blood Vessels / Q000187:drug effects* / Q000502:physiology; D003276:Contraceptives, Oral / Q000009:adverse effects*; D005260:Female; D006801:Humans; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D013927:Thrombosis / Q000209:etiology; D013929:Thromboxane B2 / Q000031:analogs & derivatives / Q000652:urine
D003276:Contraceptives, Oral; D013929:Thromboxane B2; D015121:6-Ketoprostaglandin F1 alpha; C049235:11-dehydro-thromboxane B2