A correlative study between glucocorticoid receptor levels in human mononuclear leukocytes and biochemical data in Cushing's disease.
We determined glucocorticoid receptors in human mononuclear leukocytes in 9 patients with Cushing's disease, in order to correlate them with laboratory data. Receptors were measured by a whole-cell assay method, after incubation with [3H]-dexamethasone in the presence or absence of excess unlabelled hormone. In Cushing's disease, there were 4425 +/- 364 sites/cell (N = 9), similar to in the controls: 4473 +/- 476 (N = 10); average Kd was 2.42 +/- 0.52 nmol/l (N = 3) similar to in the controls: 2.0 +/- 0.20 nmol/l (N = 3). In Cushing's patients we found significant negative correlations between basal glucocorticoid receptors and: 1) morning blood cortisol (r = -0.67, P less than 0.05), and 2) 17-ketogenic steroids after 2 mg of dexamethasone (r = -0.85, P less than 0.01). No correlations were observed with afternoon blood cortisol, free urinary cortisol, basal and post-8-mg dexamethasone 17-ketogenic steroids, TRH-TSH area, urinary calcium, plasma glucose, or systolic blood pressure.


CONCLUSIONS
In Cushing's disease, a subtle receptor down-regulation may exist, as suggested by the inverse relationship between glucocorticoid receptors and morning blood cortisol. Secondly, the relationship between basal receptors and 17-ketogenic steroids after 2 mg of dexamethasone suggests that glucocorticoid receptors in human mononuclear leukocytes could reflect the sensitivity of the nervous system-pituitary-adrenal axis to dexamethasone inhibition.
Pardes
E M
EM
División Endocrinología, Hospital Ramos Mejía, Buenos Aires, Argentina.
de Yampey
J W
JW
Soto
R J
RJ
Moses
D F
DF
De Nicola
A F
AF
D015068:17-Ketosteroids / Q000652:urine; D000293:Adolescent; D000328:Adult; D002118:Calcium / Q000652:urine; D003480:Cushing Syndrome / Q000378:metabolism*; D003907:Dexamethasone / Q000008:administration & dosage; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011965:Receptors, Glucocorticoid / Q000378:metabolism*; D013972:Thyrotropin / Q000097:blood
D015068:17-Ketosteroids; D011965:Receptors, Glucocorticoid; D003907:Dexamethasone; D013972:Thyrotropin; D002118:Calcium; D006854:Hydrocortisone