Structure-activity relationships of progesterone derivatives that bind to the digitalis receptor: Modifications in a and b rings

Biochemical Characterization of a Digitalis-Like Substance in Human Urine, Partially Purified by High Pressure Liquid Chromatography

“…In fact, Shilo et al [9] recently reported that DLI in human urine rises in response to elevations of ACTH, and falls after dexamethasone suppression, and Inagami and Tamura [10] isolated a compound showing striking similarity to the cardiac glycoside ouabain in various biological properties, from methanol extracts of bovine adrenal glands. These findings might be related to the previous reports that dehydroisoandrosterone [5] and progesterone [11] compete in a [3H] radioligand-binding assay, and so in teract at the specific cardiac glycoside-bind ing site on the receptor for Na-K-ATPase. In our extraction procedure described here, the possibility exists that corticosteroids and their conjugates can be eluated into the final fraction.…”