Effects of beta-endorphin2-9 on arginine-8-vasopressin and oxytocin levels in hypothalamic and limbic brain regions.

Immunoreactive arginine-8-vasopressin (AVP) and oxytocin (OXT) were measured in rat hypothalamic and limbic brain regions after the intracerebroventricular administration of beta-endorphin fragment 2-9 (beta E2-9). The peptide decreased the AVP content of the hippocampus and the OXT levels in the septum and amygdala. The present data favor the view that beta E2-9 interacts with limbic AVP- and OXT-systems.