title: Use of radioimmunoassay for monitoring hormonal residues in edible animal products.
abstract: Radioimmunoassay (RIA) is valuable for sensitive and specific routine measurements of hormones in body fluids. The method is also applicable to determine tissue levels of hormones which, according to tracer studies and depending on the compound, are scattered in the lower ng and pg/g range. For practical assay application it must be decided whether the parent compound or a major metabolite should be measured. Both toxicological and practical regulatory aspects have to be considered, but in any case knowledge of the metabolic profile of the compounds is necessary, especially since the specificity of the RIA group analysis is limited. When applying extraction and purification steps, differences between compounds and between tissues have to be considered; generally more difficulties are encountered than with plasma. Validation of the method should first demonstrate no unspecific interference with the antigen-antibody reaction; then the other reliability criteria have to be established. So far RIAs for the quantitation of estrogens, testosterone, progesterone, and trienbolone--a synthetic androgen--in various bovine tissue samples have been developed. The lower limit of sensitivity ranges between 10 and 70 pg/g. Quantitation of physiological levels of testosterone and progesterone is possible, but there are still some problems with estrogens.
mesh_terms: D000273:Adipose Tissue / Q000032:analysis; D000818:Animals; D002417:Cattle; D006728:Hormones / Q000032:analysis*; D007668:Kidney / Q000032:analysis; D008099:Liver / Q000032:analysis; D008460:Meat / Q000032:analysis*; D009132:Muscles / Q000032:analysis; D011863:Radioimmunoassay
chemical_list: D006728:Hormones