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SUMMARY
Fifty-two normal human placentae from the 6th to the 42nd week of pregnancy were surveyed for 3α-, 3β-, 6β-, 11α-, 11β-, 12α-, 16α-, 16β-, 17α-, 17β-, 20β-, 21- and 24-hydroxysteroid dehydrogenase (HSD) activities.
Strong NAD-linked 3β-, 16β-, and 17β-HSD activities and moderate NADP-linked 3β-, 16β- and 17β-HSD activities were found in the villous trophoblast at all ages. Weak 3α- and weak or trace 6β- and 11β-HSD activities were found in the trophoblast of some placentae using NAD as cofactor, with no obvious age distribution. Moderate 17β-HSD activity, NAD-linked only, was found in the villous stroma and vasculature.
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SUMMARY
The human pronephros showed no hydroxysteroid dehydrogenase activity. The human mesonephros, like piscine and amphibian mesonephroi had 16β- and 17β-hydroxysteroid dehydrogenase activity and a possible function of the human mesonephros is suggested. Metanephric kidneys had 3α-, Δ5-3β-, 3β-, 6β-, 16α-, 16β-, and 17β-hydroxysteroid dehydrogenases; 11β-hydroxysteroid dehydrogenase was present in all adult mammalian metanephric kidneys surveyed. 3α-Hydroxysteroid dehydrogenase was selectively present and very active in the proximal and distal convoluted tubules, particularly of the juxta-medullary glomeruli. This function is thought to be related to the excretion of 3α-ketosteroids. 11β-Hydroxysteroid dehydrogenase was confined to the collecting tubules and its possible involvement in the metabolism of cortisol, aldosterone or androgens in the kidney is noted. 17β-Hydroxysteroid dehydrogenase may be concerned in the excretion of the sex steroids; it occurs throughout the nephron. Δ5-3β-, 16α-, and 16β-hydroxysteroid dehydrogenases were not as active histochemically in the kidney as the 3α-, 3β-, 11β- and 17β-hydroxysteroid dehydrogenases.
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SUMMARY
3β-Hydroxysteroid dehydrogenase activity was studied histochemically in human, monkey, and rat adrenal glands and in human placentae. Tissue sections were incubated separately with each of the following substrates: (1) 3β-hydroxypregn-5-en-20-one (pregnenolone); (2) sodium 3β-sulphoxypregn-5-en-20-one (pregnenolonesulphate); (3) 3β-acetoxypregn-5-en-20 one (pregnenoloneacetate); (4) 3β,16α-dihydroxypregn-5-en-20-one (16α-hydroxypregnenolone); (5) 3β,17α-dihydroxypregn-5-en-20-one (17α-hydroxypregnenolone); (6) ammonium 3β-sulphoxy-17α-hydroxypregn-5-en-20-one (17α-hydroxypregnenolone ammonium sulphate); (7) 3β-hydroxyandrost-5-en-17-one (DHA); (8) 3β-sulphoxyandrost-5-en-17-one (DHA sulphate); (9) 3β-acetoxyandrost-5-en-17-one (DHA acetate); (10) androst-5-ene-3β, 17β-diol (androstenediol).
The histochemical results obtained with pregnenolone and DHA as substrates resemble those described by other workers. Using pregnenolone sulphate and 17α-hydroxypregnenolone sulphate, a strong histochemical reaction with diformazan deposition was found in the zona fasciculata of the adrenals of all species and in the placental syntrophoblast. With DHA sulphate an extremely weak histochemical reaction was obtained with the adrenal zona fasciculata, monoformazan only being deposited. The syntrophoblast, however, showed intense 3β-hydroxysteroid dehydrogenase activity when incubated with DHA sulphate. These results accord with recent findings regarding the secretion and metabolism of 3β-sulphoxysteroids.
A strong histochemical reaction was also obtained in both adrenal and placental tissues using 17α-hydroxypregnenolone, 16α-hydroxypregnenolone, androstenediol, pregnenolone acetate, and DHA acetate. These steroids have not previously been described as substrates for the histochemical demonstration of 3β-hydroxysteroid dehydrogenase in the adrenal or placenta.
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SUMMARY
11β-Hydroxysteroid dehydrogenase can be demonstrated histochemically by incubating tissues with nitro blue tetrazolium (2,2′-di-p-nitrophenyl-5,5′-diphenyl-3,3′-(3,3′-dimethoxy-4,4′-diphenylene) ditetrazolium chloride), NAD or NADP and an appropriate steroid. Suitable steroid substrates are: (1) 11β-hydroxyandrost-4-ene-3,17-dione (11β-hydroxyandrostenedione), (2) 3,11β-dihydroxyoestra-1,3,5(10)-trien-17-one (11β-hydroxyoestrone), (3) 3α,11β-dihydroxy-5α-androstan-17-one, (4) 3α,11β-dihydroxy-5β-androstan-17-one and (5) 11β-hydroxypregn-4-ene-3,20-dione(11β-hydroxyprogesterone).
11β-Hydroxysteroid dehydrogenase activity was found in the Leydig cells of six human testes from subjects ranging in age from 12 to 57 yr. with all five substrates.
The Leydig cells of the mouse testis contain demonstrable 11β-hydroxysteroid dehydrogenase activity and the volume of reactive tissue increases regularly between birth and the end of the 10th week of postnatal life; this growth curve is sigmoid in form. An extremely weak histochemical reaction with human placenta obtained at term was observed, 11β-hydroxyandrostenedione being the only substrate utilized to any extent. A specimen of hydatid mole, however, showed intense 11β-hydroxysteroid dehydrogenase activity with all substrates surveyed. 11β-Hydroxysteroid dehydrogenase was also found in the ova, granulosa, theca interna, interstitial tissue and corpora lutea of the mouse ovary.
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SUMMARY
The histochemical utilization of 3α-, 6β-, 11α-, 12α-, 16α-, 16β-, 17α-, 21- and 24-hydroxysteroids in human and mouse testis, human placenta, mouse ovary and rat adrenal has been investigated using a coupling method and the tetrazolium salt, Nitro-BT. 3α-Hydroxysteroid dehydrogenase was present in the human Leydig cells and placental syntrophoblast, but there was little in rat adrenal zona fasciculata and in mouse ovary; the enzyme is NAD or NADP dependent. 6β-Hydroxysteroid dehydrogenase was present in human Leydig cells, mouse Leydig cells, placental syntrophoblast, ova, granulosa, theca interna, corpora lutea and interstitial tissue; it is NAD dependent. 11α-Hydroxysteroid dehydrogenase activity was very poorly developed, being NAD dependent and demonstrable only in human Leydig cells. 12α-Hydroxysteroid dehydrogenase could be demonstrated in some human Leydig cells; it was both NAD and NADP dependent. 16α-Hydroxysteroids were very poorly used by all the tissues surveyed. 16β-Hydroxysteroids gave an intense histochemical reaction with NAD in human Leydig and Sertoli cells, in placental trophoblast, in adrenal zonae glomerulosa, fasciculata and reticularis and in all ovarian tissues. 17α-, 21- and 24-hydroxysteroids were poorly utilized by human Leydig cells, but not by the other tissues. The first two were NAD dependent; 24-hydroxysteroid utilization was both NAD and NADP dependent.
The techniques used are believed to demonstrate specific hydroxysteroid dehydrogenases because of variations in pyridine nucleotide requirement and in the location in the tissues of different hydroxysteroid dehydrogenases. Moreover, stereoisomers of the same hydroxysteroid behave differently in this system. The role of steroid 5α- and 5β-dehydrogenases is discussed in connexion with the histochemical results.
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SUMMARY
The histochemical utilization of 3α-, 3β-, 6β-, 11α-, 11β-, 12α-, 16α-, 16β-, 17α-, 17β-, 20α-, 21- and 24-hydroxysteroids by three normal adult human adrenal glands, two human foetal adrenal glands, three adrenals from patients with Cushing's syndrome and one adrenal adenoma are described.
The normal adult human adrenal showed high 16β-hydroxysteroid dehydrogenase activity in the zona glomerulosa. Activity restricted to the outer part of the zona fasciculata was recorded with 3α-, 3β-, 6β-, 11β-, 16α-, 16β-, and 17β-hydroxysteroids. The zona reticularis utilized 3α-, 3β-, 11β-, 16β- and 17β-hydroxysteroids less well than the zona fasciculata.
The adrenals of Cushing's syndrome showed activity only for 3β- and 16β-hydroxysteroid dehydrogenases; this activity was noted in all three zones. The activity pattern of the adrenal adenoma resembled that of the normal adult human adrenal except that greater activity for 16α-hydroxysteroid dehydrogenase was noted.
The foetal part of the human foetal cortex was extremely active, showing 3α-, 3β-, 6β-, 11β-, 12α-, 16α-, 16β-, 17β-, 20β- and 21-hydroxysteroid dehydrogenase activity. The definitive cortex behaved similarly to the adult gland and possessed 3α-, 3β-, 11β-, 16β- and 17β-hydroxysteroid dehydrogenases; some evidence of zoning of the definitive cortex was seen with the 16β-hydroxysteroid.
The relevance of these findings in the light of current knowledge of adrenal zonation is discussed.
