Synthesis of oxytocin
In du Vigneaud carried out the synthesis of oxytocin, making it the first polypeptide hormone to be synthesized.
In other words, vasopressin is secreted in spite of the presence of hypoosmolality hyponatremia when the arterial blood volume is low. The evidence of ectopic secretion is not restricted only to VP and related NP.
For example, pair- bonding behaviour in female prairie voles Microtus ochrogaster has been shown to be facilitated by infusions of oxytocin, and, in women, genetic variations in the oxytocin receptor gene OXTR have been correlated with marital quality. It is also synthesized and secreted in other tissues, including the brainuterus, placentaovariesand testes.
How much oxytocin is needed to elicit milk ejection?