Biosynthesis of Steroid Hormones	

The overall scheme of biosynthesis of steroid hormones is shown in Fig. 7.12. Although the pathways are common to the various steroids shown, specificity is achieved by specific receptors for ACTH or angiotensin, and also by the location of specific enzyme systems.  
Thus, the glomerulosa cells lack 17a-hydroxylase and do not participate in the synthesis of cortisol or androgens, for which this enzyme is essential. Conversely, fasciculata and reticularis cells lack the enzyme 18-hydroxylase and cannot synthesise aldosterone. All cells can produce deoxycorticosterone, however, since the proximal pathway is common to both of these enzyme systems.

See later:
• Hydroxylation of Steroids