Changes on hemostatic parameters induced by 17β-estradiol, ethinylestradiol, and the 17β-aminoestrogen pentolame in the male Wistar rat

• Published in: Steroids Vol. 67; no. 13; pp. 1129 - 1135
• Main Authors: Garcı́a-Manzano, Aurora, González-Llaven, José, Jaimez, Ruth, Franco, Yanira, Estela Avila, Ma, Rubio-Póo, Consuelo, Lemini, Cristina
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.12.2002; Elsevier Science
• Subjects: 17β-Aminoestrogens; Biological and medical sciences; Blood coagulation. Blood cells; Coagulation system; Estradiol; Ethinylestradiol; Fibrinogen; Fundamental and applied biological sciences. Psychology; General aspects, investigation methods, hemostasis, fibrinolysis; Molecular and cellular biology; Platelet aggregation; Ethinylestradiol; Platelet aggregation; Coagulation system; Estradiol; 17β-Aminoestrogens; Fibrinogen; Blood coagulation; Rat; Estrogen; Rodentia; 17β-Estradiol; Male; Ovarian hormone; Vertebrata; Platelet; Mammalia; Hemostasis; Animal; Sex steroid hormone; Fibrinogen: Platelet aggregation
• ISSN: 0039-128X; 1878-5867
• DOI: 10.1016/S0039-128X(02)00067-3

Oral contraceptives containing estrogens increases the incidence of thromboembolic events. In contrast, administration of 17β-aminoestrogens prolonged blood clotting time (BCT) in rodents. We studied the effect of estradiol (E 2), ethinylestradiol (EE) and pentolame on some screening hemostatic tests. BCT was evaluated 24, 48, 72 and 96 h post-treatment. Rats received subcutaneously (s.c.) for five consecutive days E 2 (0.1–1000 μg), EE (1–1000 μg), pentolame (0.1–1000 μg), or vehicle (propyleneglycol 0.3 ml). At 48 h post-treatment E 2 (1000 μg) diminished BCT (32%, P<0.01), in contrast pentolame (1000 μg) augmented BCT by 41% ( P<0.01). After 72 h, E 2 showed procoagulant effects with 10, 100 and 1000 μg doses (−45, −30, and −21%, respectively). Significant effects on BCT of EE were observed 72 h after with 1000 μg (−12%, P<0.05). Animals were treated s.c. for two consecutive days with E 2 (3 mg/100 g), pentolame (4 mg), or vehicle (0.1 ml). BCT, bleeding time (BT), platelet aggregation (PA), prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT) and fibrinogen concentration were determined. E 2 produced a significant diminution on BCT (−20%) after 72 h whereas pentolame increased BCT from 24 to 96 h (62%, maximal response at 48 h). APTT and PT coagulation times of the groups treated with E 2 and pentolame were lengthened (33 and 29%; 16 and 24%, respectively; P<0.05). Fibrinogen concentration increased (115%, P<0.01) only in the pentolame-treated group. Pentolame and E 2 produced any effects on BT and PA compared with control groups, indicating that platelet function was not modified. Our results indicate that E 2, EE and pentolame affects the plasmatic phase of the hemostatic mechanism.