<prompt> Half-life biological of oxytocin:2-3 min3-4 min5-6 min7-8 min  <response>: Oxytocin is a nanopeptide synthesised by supraoptic and paraventricular nuclei of hypothalamus. It is rapidly metabolised and degraded by oxytocinase and hence has a half life of 3 - 4 minutes and a duration of action of approximately 20 minutes. DC Sutta TB of obstetrics 8th edtn pg 573 