Two distinctive antinociceptive systems in rats with pathological pain

doi:10.1016/S0304-3940(99)00998-2

Neuroscience Letters

Volume 280, Issue 1, 11 February 2000, Pages 13-16

https://doi.org/10.1016/S0304-3940(99)00998-2 Get rights and content

Abstract

A common obstacle in clinical management of pathological pain is the poor response to opioid analgesics. We now report that Δ⁹-tetrahydrocannabinol (Δ⁹-THC)-induced antinociception remained effective in rats with pathological pain. The selective central cannabinoid receptor antagonist SR141716A, but not the generic opioid receptor antagonist naloxone, blocked the Δ⁹-THC antinociception. Moreover, there is no cross-tolerance between the antinociceptive effects of morphine and Δ⁹-THC in pathological pain states. The results indicate that Δ⁹-THC antinociception is both effective and independent of opioid receptors in rats with pathological pain. Thus, the cannabinoid analgesic system may be superior to opioids in alleviating intractable pathological pain syndromes.

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Acknowledgements

This work was supported by the PHS grant DA08835. Δ⁹-tetrahydrocannabinol was kindly provided by Dr. Bill Martin at Medical College of Virginia.

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Two distinctive antinociceptive systems in rats with pathological pain

Abstract

Section snippets

Acknowledgements

Pain

Pain

Neurosci. Lett.

Lancet

Pain

Pain

Neurosci. Lett.

Eur. J. Pharmacol.

Eur. J. Pharmacol.