Article thumbnail

Amniotic-Fluid Ingestion Enhances the Central\ud Analgesic Effect of Morphine

By Jean M. DiPirro, Alexis C. Thompson and Dr. Mark B. Kristal


Amniotic fluid and placenta contain a substance (POEF) that when ingested enhances opioid-mediated analgesia produced by several agents (morphine injection, vaginal/cervical stimulation, late pregnancy, footshock), but not that produced by aspirin injection. The present series of experiments employed quaternary naltrexone, an opioid antagonist that does not readily cross the blood-brain barrier, in conjunction with either peripheral or central administration of morphine, to determine whether amniotic-fluid ingestion (and therefore POEF ingestion) enhances opioid-mediated analgesia by affecting the central and/or peripheral actions of morphine. The results suggest that POEF affects only the central analgesic effects of morphine

Topics: Psychobiology, Physiological Psychology, Neuropharmacology, Behavioral Neuroscience
Publisher: Pergamon Press
Year: 1991
OAI identifier:

To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.

Suggested articles


  1. (1990). Amniotic fluid inges tion enhances opioid-mediated but not nonopioid-mediated analge sia.
  2. (1990). Amniotic-fluid ingestion by parturient rats enhances pregnancy-mediated analgesia. Life Sci.
  3. (1988). Dose-dependent en hancement of morphine-induced analgesia by ingestion of amniotic fluid and placenta.
  4. (1989). Enhancement of opioid-mediated anal gesia by ingestion of amniotic fluid: Onset latency and duration.
  5. Ingestion of amniotic fluid enhances opiate analgesia in rats.
  6. (1989). Involvement of the mu-opiate receptor in peripheral analgesia.
  7. J. A stereotaxic atlas of the rat
  8. Placenta inges tion enhances opiate analgesia in rats.
  9. (1982). Quaternary nar cotic antagonists' relative ability to prevent antinociception and gas trointestinal transit inhibition in morphine-treated rats as an index of peripheral selectivity. Life Sci.
  10. (1985). The use of quaternary narcotic an tagonists in opiate research.