Evidence of marked digoxin-like immunoreactivity in the human adrenal cortex: results of an immunohistochemical study.

Several lines of evidence suggest the existence, in mammalian body fluids and tissue extracts, of an as yet unidentified endogenous digitalis-like factor with potential cross-immunoreactivity with digitalis. Using anti-digoxin antibodies, we found preliminary immunohistochemical evidence of digoxin-like immunoreactivity in several human tissues. Strong reactivity was found in the adrenal cortex, which may thus represent a site of production of this endogenous factor.