High - molecular - weight
immunoreactive beta - endorphin in extracts of human placenta is a fragment of immunoglobulin G
Immunoreactive beta - endorphin was measured in the ventricular fluid of six patients with chronic pain.
Stimulation of human periaqueductal gray for pain relief increases
immunoreactive beta - endorphin in ventricular fluid
These results provide evidence of the release of human
immunoreactive beta - endorphin in vivo and suggest that naloxone - reversible pain relief achieved by stimulation of the periaqueductal gray matter may be in part mediated by the activation of beta - endorphin - rich diencephalic areas.
R. Jouppila et al., «Maternal and Umbilical Venous Plasma
Immunoreactive Beta - Endorphin Levels During Labor With and Without Epidural Analgesia,» Am J Obstet Gynecol 147, no. 7 (1983): 799 — 802.