AJP - Renal Physiology, Vol 252, Issue 3 365-F373, Copyright © 1987 by American Physiological Society
Metabolic derivatives of aldosterone
D. J. Morris and A. S. Brem
Metabolism of aldosterone during the latent period prior to the action of
the hormone may be of physiological importance. In the rat, liver
metabolizes aldosterone in a sex-dependent manner; larger quantities of
neutral polar and reduced aldosterone derivatives are found in male rat
kidney; correlating with the larger physiological responses of male rats to
aldosterone. The target tissues, mammalian kidney and toad urinary bladder,
are also capable of metabolizing aldosterone in situ to neutral polar, 5
alpha- and 5 beta-reduced, and monosulfate derivatives. The 5 alpha-reduced
metabolites possess significant antinatriuretic activity and are
preferentially synthesized by rat kidney nuclei. The metabolic pathways
leading to the synthesis of 5 alpha-reduced metabolites and their
subsequent neutral polar derivatives appear to be regulated by dietary
sodium and can be inhibited by antimineralocorticoids. At concentrations
somewhat higher than aldosterone, these 5 alpha-reduced metabolites also
can recreate the development of hypertension and suppress plasma renin
activity in young adrenalectomized spontaneously hypertensive rats. Thus,
several of the metabolically transformed aldosterone derivatives can be
correlated with physiological regulation and/or expression of the actions
of the hormone.
