Figure 1. Amino acid sequences of ovine and rat/human corticotropin-releasing factor (CRF). The amino acid sequence of ovine CRF is denoted by the open circles. Rat CRF and human CRF are identical and differ from ovine CRF by seven amino acid residues (shaded circles). Both peptides are amidated at the carboxy terminus and the amidation is essential for biological activity.