Corticotropin releasing factor-like peptides produce selective dilatation of the dog mesenteric circulation

Three synthetic peptides, ovine corticotropin-releasing factor, sauvagine, and urotensin I, contain homologous amino acid residues. In the anesthetized dog, all three produce marked and selective dilatation of the mesenteric circulation; none of the peptides influenced blood flow in the renal, femoral, carotid, or even celiac arteries. The mesenteric vasodilatation appeared to be unrelated to the common ability of these peptides to release corticotropin and beta-endorphin, and cannot be abolished or attenuated by conventional blocking agents or inhibitors. The unique action of these peptides suggests that there may be a related peptide in the intestine that acts to regulate intestinal blood flow. The peptides may also prove useful therapeutically in nonocclusive ischemia, if this unusual action is also present in humans.