Immunoreactive corticotropin-releasing factor in human plasma

J Clin Invest. 1985 Nov;76(5):2026-9. doi: 10.1172/JCI112204.


Plasma immunoreactive corticotropin-releasing factor (I-CRF) levels were determined by using a human CRF radioimmunoassay and an immunoaffinity procedure. The basal plasma I-CRF level in normal subjects was 6 +/- 0.5 pg/ml (mean +/- SD). We found that most plasma I-CRF levels were affected by stress, negative feedback, and circadian rhythm. Basal I-CRF levels were high in patients with Addison's disease, Nelson's syndrome, hypopituitarism stemming from pituitary macroadenoma, and CRF- and adrenocorticotropic hormone-producing tumors. A very low, but significant, amount of I-CRF was detected (1-3 pg/ml) in patients with Cushing's syndrome, in corticosteroid-treated patients, and in a patient with hypothalamic hypopituitarism. These results suggest that a major component of plasma I-CRF is of hypothalamic origin, however, other extrahypothalamic tissues cannot be ruled out as a minor source of plasma I-CRF.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenal Gland Diseases / blood*
  • Adrenocorticotropic Hormone / blood
  • Adult
  • Chromatography, High Pressure Liquid
  • Corticotropin-Releasing Hormone / blood*
  • Cushing Syndrome / blood
  • Humans
  • Hydrocortisone / blood
  • Hypothalamic Diseases / blood*
  • Insulin / pharmacology
  • Metyrapone
  • Pituitary Diseases / blood*
  • Radioimmunoassay


  • Insulin
  • Adrenocorticotropic Hormone
  • Corticotropin-Releasing Hormone
  • Hydrocortisone
  • Metyrapone