A RADIOIMMUNOASSAY FOR 5α-ANDROST-16-EN-3-ONE IN PORCINE ADIPOSE TISSUE

Abstract

ABSTRACT A simple and reliable radioimmunoassay (RIA) for the estimation of 5α-androstenone (5α-androst-16-en-3-one) in porcine adipose tissue has been developed. Fatty tissue samples weighing 40–60 mg were used for assay. The bulk of fat was separated from the steroid by centrifugation in an ethylacetate-ethanol solution at about −70°C. The sensitivity of the standard curve was found to be 25 pg (P < 0.01) and the smallest amount of 5α-androstenone added to adipose tissue from castrated male pigs, that can be estimated by the method, is 0.09 μg/g. Analysis of the data from the accuracy study gave the regression line y= 1.09x+2.7. The mean coefficients of variation for the inter- and intra-assay precision were 11.1 and 5.9 %, respectively. In boars (n = 9) a mean value of 2.09 μg/g adipose tissue was found (sd = 2.56). In adipose tissue from 9 female pigs and 8 castrated male pigs the level of 5α-androstenone was found to be undetectable by the present method. In adipose tissue from one castrated male pig trace amounts of 5α-androstenone were found. Fifteen samples in duplicate can be analysed by one person in 1½ days.