Affinity of 18,19-dihydroxydeoxycorticosterone and 18-hydroxy-19-nor-deoxycorticosterone to aldosterone receptor and their mineralocorticoid activity.

Affinity of 18,19-dihydroxydeoxycorticosterone (18,19-diOH-DOC) and 18-hydroxy-19-nor-deoxycorticosterone (18-OH-19-nor-DOC) to aldosterone receptor and their mineralocorticoid activity were evaluated. 18,19-DiOH-DOC (1 X 10(-6) M) did not show appreciable binding to the receptor and its relative potency as a mineralocorticoid was estimated to be less than 1/8,000 of that of deoxycorticosterone (DOC). 18-OH-19-nor-DOC bound to the receptor with an affinity similar to that of 18-hydroxydeoxycorticosterone (18-OH-DOC) or spironolactone. Its sodium retaining activity was 0.04 times as great as that of DOC and similar to that of 18-OH-DOC.