Naloxone reversal of morphine analgesia but failure to alter reactivity to pain in the formalin test
Life SciencesPublished 1 January 1978
Murray Alan North
Citations98
SJR quartileQ1
SJR score1.31
SNIP1.07
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TL;DR
These findings fail to support the hypothesis that tonic release of endogenous opioids acting at naloxone-sensitive receptors decreases sensitivity or reactivity to pain stimuli.
Abstract
Rats treated with naloxone in doses sufficient (10 mg/kg) to completely antagonize morphine analgesia showed no decrease in their thresholds of reactivity to formalin-induced chronic pain. These findings fail to support the hypothesis that tonic release of endogenous opioids acting at naloxone-sensitive receptors decreases sensitivity or reactivity to pain stimuli.
Keywords
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