Steroid binding to cardiac type I receptors: in vivo studies.
In vitro, Type I (mineralocorticoid) receptors show equivalently high affinity for aldosterone, corticosterone and cortisol in cytosol preparations from a wide range of tissues. This steroid non-selectivity is also found for hippocampal Type I receptors in vivo; in contrast, Type I receptors in physiological mineralcorticoid target tissues are highly aldosterone-specific in vivo. In the present study we show that Type I receptors in the heart are non-selective in vivo, like those in hippocampus, and therefore presumably act as high-affinity glucocorticoid receptors rather than mineralocorticoid receptors.
Pearce
P T
PT
Medical Research Centre, Prince Henry's Hospital, Melboume, Australia.
Funder
J W
JW
D000450:Aldosterone / Q000378:metabolism; D000818:Animals; D005938:Glucocorticoids / Q000378:metabolism; D007668:Kidney / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011987:Receptors, Steroid / Q000145:classification / Q000378:metabolism*
D005938:Glucocorticoids; D011987:Receptors, Steroid; D000450:Aldosterone