Ll-Deoxycorticosterone

The substrate, 11-deoxycorticosterone, was separated from the two reaction products, corticosterone (11-jS-hydroxylation) and 18-hydroxyl-ll-deoxycorticosterone (18-hydroxylation), on reversed-phase HPLC (MicroPak... 

Sample preparation 1 mL Serum + 100 pL water containing 5 p.g/mL 2,3-diaminona-phthalene and 3.5 p,g/mL IS-hydrory-ll-deoxycorticosterone + 1 mL 250 mM NaOH -I- 7 mL diethyl ether, shake on a rotary shaker for 15 min, repeat extraction. Combine the organic layers and evaporate them to dryness under a stream of nitrogen at 30-40°, reconstitute the residue in 70 p,L MeOH 100 mM perchloric acid 50 50, inject a 20 pL Ediquot. 

Drugs belonging to this class are glucocorticoids (hydrocortisone, 11-dehydrocorti-costerone, corticosterone), mineralocorticoids (aldeosterone, 11-deoxycorticosterone, ll-deoxy-17-oxycorticosterone), and sex hormons (androsterone, androstendion, estrone, progesterone). 

The ll-/3-hydroxylase found in the adrenal cortex catalyzes the hydroxylation of 11-deoxycorticosterone to corticosterone. The enzyme requires NAD as a cofactor and contains heme as the prosthetic group. 

Aldosterone and cortisol are not the only adrenal steroids with mineralocorticoid and glucorticoid activities. Corticosterone (4-pregnen-ll S,21-diol-3,20-dione), a glucocorticoid about one-fifth as active as cortisol, has little mineralocorticoid activity relative to aldosterone 11-deoxycorticosterone (DOC) (4-pregnen-21-ol-... 

The mechanism of ll hydroxylation has been examined by tracer techniques using both deuterium and oxygeu-18. No deuterium is introduced into the product when the hydroxylation (of 11-deoxy-cortisol) is carried out in D2O (335). This observation rules out mechanisms of hydroxylation in which dehydrogenation is followed by hydration, as in the prototype succinate-fumarate-malate. In confirmation of this, A -unsatiuated analogues of deoxycorticosterone are not hydroxylated by mitochondrial preparations (335). When enzymic hydroxylation is carried out in media enriched with 0 , it is found that the oxygen of the 1 l-hydroxysteroids is derived from molecular oxygen (336,724) (Table XIV). The same results have been obtained in hydroxylations carried out by microorganisms (Table XV) (72,337). 

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