This cyclic hexapeptide (FW = 774.86 g/mol; CAS 35748-51-7) corresponds to the N-terminal six amino acyl residues of vasopressin. If Phe-3 is replaced with Ile, the resulting cyclic hexapeptide, known as tocinoic acid. is identical to the N-terminal six amino acid residues of oxytocin. Pressinoic acid has no known pressor activity, perhaps as result of the loss of the carboxy-terminal tripeptide and/or the incorrect orientation of the Asn-5 side-chain This hexapeptide also activates pineal acetyl-CoA hydrolase and has a potent corticotrophin-releasing activity. Target(s): serotonin N-acetyltransferase.
