Validation of an assay to measure adrenocorticotropin in plasma and from chicken leukocytes.

A RIA for mammalian adrenocorticotropic hormone (ACTH) was modified and validated to measure chicken ACTH. The assay was capable of detecting an increase in chicken plasma ACTH following treatments known to increase plasma ACTH. Both splenic and peripheral blood leukocytes stimulated with corticotropin-releasing factor (CRF) showed a significant increase in ACTH production compared with unstimulated leukocytes. This finding supports the conclusion that the substance produced by leukocytes previously shown in our laboratory to stimulate adrenal cells to secrete corticosterone is immunoreactive ACTH.