An endogenous digitalis-factor derived from the adrenal gland: Studies of adrenocortical tumor cells

P. A. Doris, M. W. Kilgore, D. Durham, D. Alberts, D. M. Stocco

Research output: Contribution to journalArticlepeer-review

16 Scopus citations


The present studies demonstrate that the murine adrenocortical tumor cell line Y-l releases a digoxin-like immunoreactive material into both serum-supplemented nutrient medium and minimal Krebs-Ringer bicarbonate medium. Release of pregnenolone into minimal medium from these cells was consistently inhibited by addition of the cholesterol sidechain cleavage inhibitor aminoglutethimide. However, release of digoxin-like immunoreactivity (DLI) was not similarly affected. To exclude the possibility that DLI could be accounted for by cross-reaction with another known adrenal steroid, aminoglutethimide inhibition was accompanied by inhibition of 17αhydroxylase with SU-10603 and inhibition of 3β-hydroxysteroid dehydrogenase with cyanoketone. Once again, pregnenolone release was effectively inhibited, but no similar pattern of inhibition of DLI release was observed. Increasing the time of the incubation periods from 1 to 2 h did not change the pattern of secretion of pregnenolone or DLI. HPLC analysis of DLI released over prolonged culture periods into surum-supplemented nutrient medium showed high levels of DLI in a single major and several adjacent peaks. Analysis of the ability of extracts of Y-1-conditioned medium to compete with tritiated ouabain for binding to erythrocytes indicates that conditioned medium contained highly enriched levels of ouabain-like activity. On HPLC analysis, the distribution of this activity showed partial correlation with the distribution of DLI. These observations indicate that Y-l cells produce and release signilicant quantities of a material with cardiac glycoside-like properties reflected in the cross-reactivity with antidigoxin antibodies and the ability to compete with ouabain for binding to erythrocytes. In substantiation of previous findings in chopped adrenal cultures, the cardiac glycoside-like activity does not appear to result from cholesterol side-chain cleavage or pregnenolone production, since inhibition of side-chain cleavage as well as subsequent 17αhydroxylation and 3β-dehydrogenation did not result in consistent inhibition of DLI release.

Original languageEnglish
Pages (from-to)2580-2586
Number of pages7
Issue number5
StatePublished - Nov 1989

ASJC Scopus subject areas

  • Endocrinology


Dive into the research topics of 'An endogenous digitalis-factor derived from the adrenal gland: Studies of adrenocortical tumor cells'. Together they form a unique fingerprint.

Cite this