title: Radioimmunoassay for serum levels of an anti-androgen TSAA-291 (Oxendolone) in rats.
abstract: A simple radioimmunoassay method was established to determine serum levels of a steroidal anti-androgen, TSAA-291 (Oxendolone, 16 beta-ethyl-17 beta-hydroxy-4-estren-3-one) utilizing ether-extract of serum. Using an antiserum raised against TSAA-291-3-oxime-BSA conjugate in a rabbit, a standard curve was obtained in the assay range from 30 pg to 12 ng/tube. Intra- and inter-assay coefficients of variation were calculated to be 11 and 21%, respectively. Recovery rate of unlabeled TSAA-291 was 84%. Cross-reaction with endogenous steroids was less than 0.2%. TSAA-291 estimates were compared with those determined after further purification on a Celite column, or with those assayed with a gas-liquid chromatograph. The difference between these estimates was less than 16 and 25%, respectively, suggesting little contribution of the metabolites of TSAA-291 to the estimates by the radioimmunoassay. After successive treatments of male rats with TSAA-291 in an aqueous suspension in daily doses of 5, 15 and 50 mg/kg body weight for two weeks, serum TSAA-291 levels were determined by the radio immunoassay and calculated to be 22.7, 76.9 and 194.9 ng/ml, respectively.
mesh_terms: D000818:Animals; D002849:Chromatography, Gas; D008297:Male; D009277:Nandrolone / Q000031:analogs & derivatives* / Q000097:blood / Q000494:pharmacology; D009929:Organ Size / Q000187:drug effects; D011467:Prostate / Q000187:drug effects; D011863:Radioimmunoassay / Q000379:methods; D051381:Rats; D011919:Rats, Inbred Strains; D012669:Seminal Vesicles / Q000187:drug effects; D013737:Testis / Q000187:drug effects
chemical_list: D009277:Nandrolone; C005671:oxendolone