INVESTIGADORES
GALIGNIANA Mario Daniel
artículos
Título:
Features of the shuttle pair 11 beta-hydroxyprogesterone-11-ketoprogesterone
Autor/es:
GALIGNIANA MD, VICENT GP, BURTON G, LANTOS CP
Revista:
STEROIDS
Editorial:
ELSEVIER SCIENCE INC
Referencias:
Lugar: Amsterdam; Año: 1997 vol. 62 p. 358 - 364
ISSN:
0039-128X
Resumen:
11 beta-hydroxyprogesterone (HOP) and 11-ketoprogesterone (KP) are
reversible components of a shuttle pair whose interconversion in rat
liver is catalyzed by isoform-1 of 11 beta-hydroxysteroid dehydrogenase.
Kidneys also produce this interconversion. The present study was
carried out to investigate the shuttle pair and its components in the
rat. As in corticosterone/11-dehydrocorticosterone, oxidation is more
effective at an alkaline pH, while reduction prevails at a neutral pH.
Moreover, both reactions are inhibited by the detergent 3-[(3-cholamido
propyl)-dimethylammonio]-1-propane-sulphonate (CHAPS). However, at
variance with the 11-ketosteroids cortisone (E) and
11-dehydrocorticosterone (A) thought to be "inactive," KP has slight
direct Na(+)-retaining properties, and it, as well as HOP, induces
glucocorticoids (11 beta-hydroxycorticoids) to retain sodium.
11-ketoprogesterone exhibits 17 times better affinity for native type 1
mineralocorticoid receptor than HOP and a 3-fold affinity for partially
purified (transcortin free) mineralocorticoid receptor. However, KP, in
contrast to HOP, binds only weakly to transcortin, not at all to
glucocorticoid receptor, and requires reduction at C11 for tyrosine
aminotransferase (TAT) induction.