Abstract
The possibility that dehydroepiandrosterone (DHEA) is metabolized in
human plasma was studied by column and thin-layer chromatography. The results
obtained indicate that a time-dependent disappearance of DHEA is matched by the
appearance of newly-formed species that may represent DHEA conversion
by-products. Neither disappearance of DHEA, nor formation of the alleged
conversion by-products was observed when reactions were performed under
conditions in which plasma enzymes were removed or inactivated. These results
suggest that, in plasma, DHEA is partially transformed into different
substances, and that the conversion reactions are catalyzed by enzymes present
in this tissue. The observed kinetics of appearance and partial disappearance
of the radiolabeled species can be interpreted as indicating that some of the
by-products formed are further converted into other substances. The data shown
appear to indicate that plasma can be added to the list of the already known
compartments that are involved in steroid metabolism.
Key words
Steroids - Metabolic Conversion - Enzymes - Human Blood
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L. G. Roda
Dipartimento di Neuroscienze
Università degli Studi di Roma Tor Vergata · Via
Montpellier 1 · 00133 Roma · Italia
eMail: lgroda@libero.it