ADRENAL BIOGENESIS IN VIVO OF ANDROGENS AND CORTISOL IN THE GUINEA-PIG USING A CONTINUOUS INFUSION TECHNIQUE

Abstract

SUMMARY An in-situ continuous infusion technique was used to study the biogenesis of androgens and cortisol in the guinea-pig adrenal gland after the infusion of 3 H- and 14C -labelled precursors of these compounds. Pregnenolone was converted to 17α-hydroxypregnenolone, progesterone, 17α-hydroxyprogesterone and cortisol. The results of infusion of a combined dose of [ 3 H]17α-hydroxypregnenolone and [ 14 C]progesterone indicated that the major pathway to cortisol is via 17α-hydroxypregnenolone. No conclusive proof could be obtained regarding synthesis of dehydroepiandrosterone or androst-4-ene-3,17-dione. The only androgen detected in the guinea-pig adrenal venous blood was 11β-hydroxyandrost-4-ene-3,17-dione. The major and minor biosynthetic pathways involved in the synthesis of these hormones are discussed.