title: Vasoconstrictory thromboxane A2 and vasodilatory prostacyclin in climacteric women: effect of oestrogen-progestogen therapy.
abstract: The production of vasoconstrictory thromboxane A2 (TxA2) and vasodilatory prostacyclin ( PG2 ) was studied in women suffering from climacteric vascular instabilities before and during the oestrogen-progestogen therapy. The serum concentrations of TxB2, a metabolite of TxA2, in climacteric patients were similar (170.5 +/- 25.5 ng/ml, mean +/- SE, n = 14) to those in control subjects (196.0 +/- 27.5 ng/ml n = 17) before the start of treatment, but rose to 209.3 +/- 24.5 ng/ml after 3 wk of treatment (P less than 0.01 in comparison with the pre-treatment level), to 227.2 +/- 44.1 ng/ml after 3 mth (P less than 0.05) and to 237.4 +/- 30.3 ng/ml after 6 mth (P less than 0.05). The plasma concentrations of 6-keto-prostaglandin F1a , a stable breakdown product of PG2 , were normal in climacteric (43.5 +/- 7.3 pg/ml as against 46.1 +/- pg/ml) and did not change during replacement therapy. It was concluded, firstly, that climacteric symptoms are not accompanied by changes in TxA2/ PG2 which can be detected in peripheral blood and, secondly, that the increase in the concentration of vasoconstrictory TxA2 induced by oestrogen-progestogen therapy may contribute to the disappearance of climacteric vascular instabilities.
mesh_terms: D015121:6-Ketoprostaglandin F1 alpha / Q000097:blood; D000328:Adult; D002979:Climacteric / Q000187:drug effects*; D003277:Contraceptives, Oral, Combined / Q000494:pharmacology / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D011464:Epoprostenol / Q000096:biosynthesis*; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D005260:Female; D006801:Humans; D016912:Levonorgestrel; D008875:Middle Aged; D009640:Norethindrone / Q000494:pharmacology* / Q000627:therapeutic use; D009644:Norgestrel / Q000494:pharmacology* / Q000627:therapeutic use; D013928:Thromboxane A2 / Q000096:biosynthesis*; D013931:Thromboxanes / Q000096:biosynthesis*
chemical_list: D003277:Contraceptives, Oral, Combined; D013931:Thromboxanes; D009644:Norgestrel; D004958:Estradiol; D013928:Thromboxane A2; D015121:6-Ketoprostaglandin F1 alpha; D016912:Levonorgestrel; D011464:Epoprostenol; D009640:Norethindrone