Radioimmunoassay of unconjugated plasma ethynylestradiol in women given a single oral dose of ethynylestradiol or mestranol.
A method for the radioimmunoassay of ethynylestradiol in plasma is described. The sensitivity is 18 pg/ml, recovery 86.5%, and precision 10.9% (coefficient of variation). Normal women, five at each dose level, were given 50 or 80 mug ethynylestradiol or 50, 80, or 100 mug mestranol of uniform bioavailability. Peak plasma levels were consistently obtained in the 1-hour plasma sample with the former compound. With mestranol, the peak levels of ethynylestradiol were lower than with the same quantity of ethynylestradiol and the time-curve of plasma levels much more variable. With this procedure, it is now possible to study certain aspects of the pharmacokinetics of these clinically important compounds.
D000284:Administration, Oral; D000918:Antibody Specificity; D004305:Dose-Response Relationship, Drug; D004997:Ethinyl Estradiol / Q000008:administration & dosage / Q000097:blood* / Q000494:pharmacology; D005260:Female; D006801:Humans; D008656:Mestranol / Q000008:administration & dosage / Q000494:pharmacology*; D011863:Radioimmunoassay; D013997:Time Factors
D004997:Ethinyl Estradiol; D008656:Mestranol