Ingested bovine amniotic fluid enhances morphine antinociception in rats

Corpening, James W. and Doerr, Jean C. and Kristal, Dr. Mark B. (2000) Ingested bovine amniotic fluid enhances morphine antinociception in rats. [Journal (Paginated)]

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Ingestion by rats of rat placenta or amniotic fluid enhances opioid-mediated, or partly opioid-mediated, antinociception produced by morphine injection, vaginal or cervical stimulation, late pregnancy, and foot shock. This phenomenon is believed to be produced by a placental opioid-enhancing factor (POEF). Ingestion by rats of human or dolphin placenta has also been shown to enhance opioid antinociception, suggesting that POEF may be common to many mammalian species. We tested bovine amniotic fluid (BAF) for its capacity to enhance morphine antinociception in female Long-Evans rats, as determined by percentage change from baseline tail-flick latency in response to radiant heat, and we report that 0.50 mL BAF effectively enhanced morphine antinociception but did not by itself produce antinociception. The efficacy of POEF across species suggests that POEF may have been functionally (and structurally) conserved during evolution. Furthermore, the availability of POEF at parturition, as well as its ability to enhance pregnancy-mediated antinociception without disrupting maternal behavior, offers a tenable explanation for the long-debated ultimate causality of placentophagia.

Item Type:Journal (Paginated)
Keywords:Antinociception, Morphine, Opioids, Afterbirth, Amniotic fluid, Placenta, Bovine, Pain, Tail-flick, Rats
Subjects:Biology > Behavioral Biology
Psychology > Psychobiology
Psychology > Physiological Psychology
Biology > Animal Behavior
Neuroscience > Behavioral Neuroscience
Neuroscience > Neurochemistry
ID Code:6250
Deposited By: Kristal, Mark B.
Deposited On:02 Nov 2008 10:00
Last Modified:11 Mar 2011 08:57


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