Figure 3:The role of the mitochondrion in the adrenal stereoidogenesis.Another pathway in this sequence of enzymatic reactions is the convertion of 17α-hydroxyprogesterone to androstenedione by the enzyme 17,20 lyase. In addition, 17α-hydroxypregnenolone can be converted to dehydroepiandrosterone (DHEA) by the action of the enzyme 17,20 lyase. DHEA is then converted to DHEAS sulfate by a reversible adrenal sulfokinase. DHEA is also converted to androstenedione by 3β-hydroxysteroid dehydrogenase. Androstenedione can be converted to testosterone, although adrenal secretion of this hormone is minimal (11,12,13) (figure 4).