Ovine Corticotropin Releasing Hormone Stimulation Test: Normal Value Study

We determined the pituitary-adrenal response to 1 μg/kg of ovine corticotropin releasing hormone (oCRH) administered as an intravenous bolus injection in 50 normal subjects. Brief facial flushing was noted in 44% of the subjects; no other side effects were reported. Plasma corticotropin levels increased from a median of 30.2 pg/ml at baseline to a median peak level of 77.8 pg/ml after administration of oCRH; the peak response occurred at the 30- to 45-minute or the 45- to 60-minute time point. Plasma cortisol levels increased from a median of 10.8 μg/dl at baseline to a median peak level of 22.0 μg/dl after administration of oCRH; the peak response occurred at the 45- to 60-minute time point. Plasma β-endorphin levels increased from a median of 9.5 pg/ml at baseline to a median peak level of 23.0 pg/ml after administration of oCRH; the peak response occurred at the 15- to 30-minute or the 30- to 45-minute time point. The responsiveness to oCRH was unaffected by age, sex, or body mass index of the subjects.