Pregnenolone sulfate transformation

Finally, a precise clinical use of pregnenolone sulfate can be considered since this compound seems to be active in depressing uterine contractility, without being previously transformed into progesterone (Scom-megna et al, 1970). With respect to possible hormonal control of cancer, Libby and Dao (1970) have indicated that certain breast tumors, which do not regress after adrenalectomy, lack sulfate-activating enzymes. 

Pregnenolone is extensively metabolized by the different fetal tissues. After fetal perfusion, this compound is transformed into pregnenolone sulfate in all the fetal tissues, into 17a-hydroxypregnenolone, dehydroepian-drosterone, and deliydmepiandrosterone sulfate principally in the adrenal tissues, and into 20a-dihydropregnenolone and 20a-dihj dropregiienolone sulfate mainly in fetal liver (Solomon et al 1907). 

Pregnenolone sulfate is princip iy secreted from the fetus to the placenta in this compartment most of this conjugate is hydrolyzed and transformed into progesterone, and a small part crosses to the mother as... 

Fig. 18. Schematic representation of the principal transformations of the Cu and Cl steroids and their conjugates in the fetal and placental compartments. Aj-P pregnenolone P progesterone ITd-IlO-Aj-P iTa-hydroxyprcgnenolone 17a-HO-P 17a-hydroxyprogesterone DTI A dehydroepiandrosterone AND androstenedione 17/J-.D1I-DHA androstenediol-lTp DIIA-S dehydroepiandrosterone sxilfate Ida-IIO-DHA 16a-hydroxydchydrocpiandrosterone 16 -1I0-D1IA-S 16a-hydroxydehydroepi-androstcrono sulfate androstenetriol-S androstenetriol sulfate E estriol Kj-S estriol sulfate T testosterone Ej estradiol Kj-S estradiol sulfate E[ estrone E -S estione sulfate.

---