RESUMO
We have developed a non-isotopic TR-FIA for Cyproterone acetate and Cyproterone in plasma. Synthesis of the biotinylated tracers, biotinylated Cyproterone acetate, and Cyproterone, as well as the preparation of anti-Cyproterone acetate and anti-Cyproterone antisera are reported. The specificity of anti-Cyproterone acetate antiserum resulting from the coupling of link bridge (link bridge between steroid and BSA), on the 3-position on the steroid skeleton, allowed to carry out the Cyproterone acetate assay directly on extracted plasma (without chromatography). On the other hand Cyproterone assays require a purification step, including extraction plus chromatography, because the plasma Cyproterone acetate concentrations in Cyproterone acetate-treated women are 200 times higher than for Cyproterone. Theses plasma TR-FIA of Cyproterone acetate and Cyproterone presented the advantage of needing only small doses of radioactivity for recovery controls, and better practicability related to the only existing RIA described to date.
Assuntos
Análise Química do Sangue/métodos , Acetato de Ciproterona/sangue , Ciproterona/sangue , Fluorimunoensaio/métodos , Acne Vulgar/sangue , Acne Vulgar/tratamento farmacológico , Animais , Especificidade de Anticorpos , Análise Química do Sangue/normas , Análise Química do Sangue/estatística & dados numéricos , Ciproterona/imunologia , Acetato de Ciproterona/imunologia , Acetato de Ciproterona/uso terapêutico , Feminino , Fluorimunoensaio/normas , Fluorimunoensaio/estatística & dados numéricos , Hirsutismo/sangue , Hirsutismo/tratamento farmacológico , Humanos , Coelhos , Padrões de Referência , Sensibilidade e EspecificidadeRESUMO
Previous reports speculated that vascular events could be related to the development of antibodies against synthetic steroids contained in oral contraceptives or other hormonal treatments. This study describes original immunoassays designed to detect antisynthetic steroid antibodies. In a first step, the assays were characterized and validated using animal-raised antisteroid antibodies. In a second step, a population of 88 oral contraceptive users, 47 of them having developed a vascular thrombosis during synthetic steroid use and 41 serving as healthy control users, were tested. Detection of antibodies against ethinylestradiol, levonorgestrel, norethisterone, cyproterone acetate, and gestodene showed that the values obtained in normal oral contraceptive users as well as thrombosis patients are very low, and show no statistically significant difference between the two groups tested. Taken together, these data indicate that the "immunological hypothesis" related to antisteroid antibodies is unlikely to explain the pathogenesis of vascular events in oral contraceptive users.