THE EFFECTS OF CORTICOTROPIN RELEASING FACTOR ON THE ANTERIOR PITUITARY FUNCTION OF STALK-SECTIONED CYNOMDLGUS MACAQUES: DOSE RESPONSE OF CORTISOL SECRETION

The recent identification of ovine corticotropin releasing factor (CRF), a 41-amino acid peptide, provides a potential new approach to evaluate disorders of the hypothalamic-pituitary-vadrenal axis. We report here the effects of this new factor in the pituitary stalk-sectioned cynomolgus macaque. Given as an intravenous bolus, CRF stimulated cortisol secretion with an ED50 between 0 .1 and 1 μg⁄kg body weight. The peak cortisol response occurred after 15-30 min at low doses (0.5 - 1 μg⁄kg) and after 45-90 min at higher doses (2-40 μg⁄kg). This factor also stimulated the release of growth hormone and prolactin, but had no effect on TSH or LH secretion.