Gastric vagotomy blocks opioid analgesia enhancement produced by placenta ingestion

Tarapacki, J. A. and Thompson, A. C. and Kristal, Dr. Mark B. (1992) Gastric vagotomy blocks opioid analgesia enhancement produced by placenta ingestion. [Journal (Paginated)]

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Ingestion of amniotic fluid or placenta by rats has been shown to enhance opioid-mediated analgesia induced by morphine injection, footshock, vaginal/cervical stimulation, or late pregnancy. This enhancement by ingestion appears to be specific to the central actions of opioids. The present study was designed to examine the possibility that information traveling via the vagus nerve might be involved in mediating this effect. Rats that had undergone either selective gastric vagotomy or sham vagotomy were injected with either morphine sulfate or vehicle and fed either placenta or a meat control. Enhancement was observed in rats that had undergone sham vagotomy but not in those that had undergone gastric vagotomy. These results support an interpretation of vagal involvement in the enhancement of opioid-mediated analgesia by placenta.

Item Type:Journal (Paginated)
Keywords:placenta, opioids, morphine, POEF, vagotomy, placentophagia, pain, analgesia, antinociception, tail-flick latency, vagus, rat
Subjects:Psychology > Physiological Psychology
Neuroscience > Behavioral Neuroscience
Neuroscience > Neurochemistry
ID Code:5800
Deposited By: Kristal, Mark B.
Deposited On:13 Nov 2007 01:06
Last Modified:11 Mar 2011 08:56


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