Melatonin and glucocorticoid hormones.
The synthetic glucocorticoid dexamethasone (2.5, 5 or 10 micrograms/day), administered in the drinking water for 7 days, significantly reduced body weight gain, thymus weight and adrenal weight in female rats. Concomitant administration of melatonin (0.2 or 1.0 mg, i.p.) at either 8.00 or 16.00 h did not alter the glucocorticoid effect on any of these parameters. In competition binding studies melatonin did not compete with 3H-dexamethasone for binding to glucocorticoid receptors in thymus cytosol from adrenalectomized rats. By these indices, therefore, melatonin does not appear to be a glucocorticoid antagonist.
Familari
M
M
Medical Research Centre, Prince Henry's Hospital, Melbourne, Victoria, Australia.
Funder
J W
JW
D000315:Adrenalectomy; D000818:Animals; D001667:Binding, Competitive; D003907:Dexamethasone / Q000037:antagonists & inhibitors / Q000378:metabolism; D005260:Female; D005938:Glucocorticoids / Q000037:antagonists & inhibitors* / Q000378:metabolism; D008550:Melatonin / Q000378:metabolism / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011965:Receptors, Glucocorticoid / Q000378:metabolism
D005938:Glucocorticoids; D011965:Receptors, Glucocorticoid; D003907:Dexamethasone; D008550:Melatonin