Abstract # 4253 Event # 4:

Scheduled for Thursday, June 21, 2012 10:30 AM-10:55 AM: Session 1 (Magnolia) Keynote Address


K. J. Parker
Stanford University School of Medicine, Department of Psychiatry and Behavioral Sciences, 1201 Welch Rd., MSLS P-104, Stanford, CA 94305-5485, USA
     The nonapeptide oxytocin plays a critical role in mammalian reproductive and social behaviors including lactation and social bonding. Oxytocin is widely believed to be present and structurally identical in all placental mammals, ranging from rodents (Rattus and Mus genera) to rhesus monkeys (Macaca mulatta) to humans (Homo sapiens). Less is known about New World monkey oxytocin behavioral biology. Recent pharmacological studies using the conserved oxytocin peptide have demonstrated both behavioral and neuroendocrine effects in marmosets (Callithrix penicillata) and squirrel monkeys (Saimiri sciureus), respectively. But efforts to quantify oxytocin concentrations in blood and cerebrospinal fluid using established assay techniques have been largely unsuccessful. This failure led my group to sequence the squirrel monkey oxytocin gene, and led to the discovery that multiple species of New World monkeys possess a novel form of oxytocin, [P8] oxytocin. This mutation arises from a substitution of a leucine to a proline in amino acid position 8. Further analysis of this mutation in squirrel monkeys indicates that [P8] oxytocin is transcribed and translated properly. This mutation is specific to oxytocin, as the peptide sequence for arginine vasopressin, a structurally related nonapeptide, is unaltered. These findings dispel the notion that all placental mammals possess a “universal” oxytocin sequence, and highlight the need for research on the functional significance of this novel nonapeptide in New World monkeys.