THE ESTIMATION OF CORTISOL AND CORTISONE IN BOVINE AND OVINE PLASMA

Abstract

SUMMARY The quantitative estimation of cortisol and cortisone in ruminant jugular vein plasma using the soda fluorescence reaction on paper is described. For plasma volumes of 50 ml. or less a partial purification of the plasma extract on a florisil column gave a fraction pure enough for paper chromatography and fluorimetry. The method was used to determine plasma concentrations of adrenal steroids in wethers after injections of either ACTH or cortisol acetate. Extracts from 100 ml. or more of plasma required a further step, namely gradient elution chromatography, to give fractions suitable for fluorimetry on paper. Satisfactory recoveries from 100 ml. plasma of 1 μg. and 0·5 μg. cortisone and cortisol were obtained. The cortisol concentration in pooled bovine plasma was 0·5 μg./100 ml. and that for ovine plasma 1·45 μg./100 ml. In both cases cortisone was just detectable. Corticosterone could not be detected in bovine plasma.