APPLICATION OF RADIORECEPTOR ASSAYS FOR SYSTEMATIC TOXICOLOGICAL ANALYSIS .2. THEORETICAL CONSIDERATIONS AND EVALUATION

In this paper the applicability ot radioreceptor assays tor systematic toxicological analysis will be evaluated on a theoretical basis as we ll as on the basis of the outcomes of the analysis of a large number o f urine samples collected after administration of a selected number of drugs to healthy volunteers and patients. Many drugs and other substa nces of toxicological relevance exert their action through an interact ion with one or more receptor (sub)types. Whether the number of person s are using particular drugs intentionally of unintentionally, radiore ceptor assays can be a useful tool for systematic toxicological analys is in that they can be applied to the identification ot entire pharmac ological classes of substances as well as pharmacologically active met abolites. In part 1 of this paper detailed procedures for radiorecepto r assays for benzodiazepines, anticholinergics and antihistaminics hav e Deen described in detail in order to illustrate not only the potenti als but also the limitations of assay conditions. Fifteen drugs were a dministered to patients and volunteers and urine samples were collecte d and determined with the three radioreceptor assays. The results ot t his study underline the theoretical applicability ot receptor assays i n systematic toxicological analysis though sample pretreatment procedu res may contribute to an improvement in sensitivity and applicability to other biofluids.